Developer community

2020’s most popular KaiOS apps

Lots happened in the KaiStore in 2020. We added new features and grew the collection of apps to more than 800, thanks to our developer community and the Ecosystem team’s tireless efforts.

Now that the year is officially behind us, we’ve compiled three app top 5 lists in the following categories for you:

  • Most installed apps
  • Most installed games
  • Staff picks

Most installed apps 📈

To determine the most installed apps on KaiOS devices in 2020, we’ve looked at all the install data from devices outside of India (as those run their own JioStore). We’ve also excluded apps preloaded on most phones, such as WhatsApp, Facebook, YouTube, and the Google apps. Lastly, the list doesn’t include games, as we’ve given those their own category (see next section).

Here are the top 5 of most installed apps on KaiOs smart feature phones in 2020.


Developer: Xender

This cross-platform file transfer sharing app takes the top spot for downloads in 2020. Xender’s top-ranking shows just how popular file-sharing is in emerging markets, especially music and video files. Its compatibility between KaiOS smart feature phones and Android smartphones doesn’t hurt either.

UC Browser

Developer: Alibaba

This browser provides a fast, all-in-one web experience and is a long-time favorite in emerging markets like India. Available on the KaiStore since October 2019, it provides a great way to explore the internet on a smart feature phone.

Ringtones Free

Developer: Warren Miller

Since the dawn of mobile phones, people have loved to personalize their devices with ringtones. Smart feature phone users are no different, and Ringtones Free by indie developer Warren Miller is proof with an impressive third ranking in the 2020 installs.


Developer: Zhang Qichuan

To ensure a fast and responsive Twitter experience on KaiOS, indie developer Zhang Qichuan created Tweetfit. Using the public Twitter API, he has created an excellent tweeting experience for everyone on KaiOS phones, and Tweeps are clearly loving it.

PDF Reader

Developer: Bartlomiej Tadych

We close the top 5 with a third indie developer. Bartlomiej Tadych realized many people need to open a PDF on their phones regularly. With his PDF Reader app, he optimized this experience for the smaller screens of smart feature phones, ensuring people can read their PDFs on KaiOS.

Most installed games 🎮️

With 500+ games available in the KaiStore, we figured they deserved their own category. Here we see lots of innovation and exciting things happening, with both indie developers and a large studio present on the list.

Here are the top 5 of most installed games on KaiOS smart feature phones in 2020.

Drift Rally

Developer: Blacksheep Games

Car racing is what people love to do on their smart feature phones. In this fun and fast-paced game, the middle 5 button is your best friend. Use it to swap lanes and survive the incoming enemy cars driving right at you. Otherwise… a car crash and game over!

Danger Dash

Developer: Gameloft

This runner game is the runner-up in our most installed games of 2020 category. Use D-Pad Up/Left/Right/Down or press 2/4/6/8 to make your character jump and dash through the jungle. Survive scores of obstacles in a lost city, and hold on for dear life when you reach the mysterious temple…

123 Fruit Smash

Developer: Blacksheep Games 

ANOTHER top three entry for developer Blacksheep Games! Besides Drift Rally at number one, smashing and slicing watermelons has brought their title 123 Fruit Smash the third position in this year’s ranking. In this game, you must smash the green watermelons and avoid hitting the red ones, all within the designated time limit. Do you have the ninja skills to win this one?

3D Football Pong Deluxe

Developer: Alex Marc

Alex Marc brings us 3D Football Pong Deluxe, which brings him this fourth place in our ranking. You’re up against artificial intelligence and have to put in as many goals as you can. How high can you get your score?

Siberian Strike

Developer: Gameloft

We’re not done with double entries in this year’s ranking. Gameloft also takes home another position, closing the top 5 with Siberian Strike. It’s a retro-style, aerial combat game in which you face off against challenging bosses in massive aircraft. Exciting combat and cool upgrades to make your planes stronger ensure hours and hours of fun well beyond 2020.

Staff picks 🏅

Popularity is only one way to measure. Fewer downloads don’t necessarily mean an app is not great. Naturally, our team sees and tries all the apps that come in; here are some of our favorites from 2020.

Magic Photo

Developer: Nubilion
Category: Entertainment

A complete photo editor with all the tools you need, like color adjustments, cropping, stickers, and filters. You can save the pictures and share them with friends and family. The app runs smoothly on all KaiOS devices, including those with 256MB memory.


Developer: PodLP
Category: Social

The first podcast app designed and developed specifically for KaiOS. We especially like that you can listen online as well as offline. The developer also deserves a special shoutout for continuously improving and updating the app and putting in extra effort to support multiple languages.


Developer: WikiHow
Category: Books & Reference, Education

An excellent and practical guide on almost anything, providing valuable knowledge to all people with KaiOS phones. We also partnered with the WikiHow team to create dedicated content for first-time internet users on how to use KaiOS smart feature phones.


Developer: Valeriy Skachko
Category: Health, Education

The first app released on the KaiStore in March to provide COVID information to KaiOS users. The app is available in eight languages and provides the latest info and data from trusted health organizations.

Klondike Solitaire

Developer: Taara Games
Category: Games

A recently released game that’s clocking in an extraordinary amount of downloads. If the title was released a bit earlier in the year, we’re quite sure this one would have been in the games top 5. We’re not surprised, though, as developer X has created a portfolio of quality apps, with more than two 2 million game plays across all his titles in less than a year.

On to 2021

That’s it for 2020’s most popular apps and staff picks. We can’t wait to see what 2021 will bring. In the meantime, have a look at all the available KaiOS devices here in case you don’t have a smart feature phone yet. And if you got inspired and want to get yourself on the 2021 list, make sure to head over to this blog post: Learn to develop for the KaiOS operating system with these resources.

Developer community

KaiOS developer team gets active on Reddit

As of today, the KaiOS developer team will become more active in the KaiOS developer subreddit, the community on the social media website Reddit dedicated to KaiOS development.

Our developers will help maintain r/KaiOS by sharing developer updates and answering questions posted by community members.

Rather than act as moderators, they will participate as community experts, providing support and information as needed. They will not remove posts, ban users, or enforce site rules. 

To ask questions or share feedback directly with the KaiOS developer team, community members can use the flair options “development” and “feedback”.

We’re excited to work more closely with the Reddit community to better serve our developers and our users.

Join us on Reddit:


Developer community

App Simplicity: Build KaiOS apps to become a better developer

Have you heard of Hemingway’s famous six-word story? He was challenged to tell a complete story in as few words as possible. For sale: Baby shoes, never worn.

The power is in its simplicity. It’s an example of the psychology of creative limitation — purposely applying constraints to the creative process.

This method has been used successfully in everything from writing to design and can be useful in app development as well. Smart feature phone applications require a level of simplicity that native apps do not, challenging developers to use the power of app simplicity to their advantage.

We talked to a few app developers about their experience building web apps for KaiOS and discovered several ways that creating engaging and helpful apps with fewer resources helps them grow as developers.

App simplicity makes you think creatively

Staring at a blank monitor can be overwhelming because the options feel limitless. Many developers find that having constraints, such as having to design for smaller screens or for navigation via a physical keypad rather than a touchscreen, inspires them to get creative.

Developer Eli Shulga believes app simplicity helps keep him on course: “The simplicity in the process helps me psychologically. It’s easier to stay in the scope [of the app].”

While he always has the urge to do more, the limitations continually encourage him to scope down and narrow his focus.

Christian Waadt says, “The most difficult part was to figure out how to build a proper app for a phone without a touchscreen.”

While the limitation was challenging, Waadt wanted to see if he could build a 3D game for KaiOS devices.

Not only did Waadt succeed, he now documents his 3D game development progress on Twitter and shares advice on his website.

Ben Simms also enjoyed thinking beyond touchscreens. “It sort of forced me to think creatively about the games and how you can make them work with buttons and still make it enjoyable for people,” he said.

Another KaiOS developer came up with an interesting way to use the physical keypad. His retro platformer game is played by turning the device on its side and using the keypad like a console controller.

Bringing console-quality games to KaiOS! I’ve published retro platformer XRick to the store. from KaiOS

KaiOS developers don’t just find innovative ways to work with keypads and smaller screens – they also work out how to deliver engaging apps that require fewer resources from the device itself.

Smart feature phone applications teach you to optimize app performance

Apps in the KaiStore must be smaller than 6MB, so developers must find ways to deliver an engaging experience for users while working with limited performance capabilities.

Shulga, known for his hand-drawn animations, likens his approach to removing pages from a flipbook.

“I see if I can do the animation with fewer frames,” explains Shulga. “If it’s done quickly and with the right movement, I can save on performance by cutting animation in a fast movement and saving it for a different part of the app. It’s like a bonus performance!”

“Developing apps for KaiOS is a new level,” says Christian Waadt. While the limited runtime performance was a major challenge, he claims developing for KaiOS encouraged him to improve his rusty JavaScript skills and come up with tricks to optimize the performance of his apps.

Web apps force you to think about how users interact with simpler hardware

Getting people to download an app and keep using it is hard – 60% of downloaded apps are opened less than 10 times before users give up on them. KaiOS developers say that building simple feature phone applications helps them prioritize the user experience.

Smartphones have so much screen real estate that apps can get very complex. Gabriel Rotaru says the smaller screens and physical keypads on KaiOS devices make him approach app development with a simpler outlook for the sake of the user.

“Every step is a key press,” he explains, “so you must construct the user interfaces differently to make sure the user has a good experience.”

For his game app, Guess the Logo, Rotaru used A/B testing to see how to encourage users to keep playing. He discovered that allowing players to skip levels made the game too easy, but without it, users became frustrated and quit playing.

In the end, Rotaru added a hint button and the option to skip a level after a certain number of incorrect answers. Focusing on the user experience helped him fine-tune his game and increase engagement.

Building feature phone applications made him realize that although he can make complex apps, that’s not necessarily what users want. It’s all about finding a balance.

Screenshots of Guess the Logo

When adapting an Android game for KaiOS, Ben Simms also started by thinking about how the user would hold the phone and interact with the game. In the end, he used the portrait orientation of KaiOS devices to his advantage and created a fishing game that leveraged the length of the screen to show fish deeper in the water.

Get creative with KaiOS

Working with hardware and software limitations can push you to come up with new ideas for engaging content. Smart feature phone applications can’t hide behind flashy features or elaborate design––their success relies on core functionality.

American jazz bassist Charles Mingus once said, “Making the simple complicated is commonplace; making the complicated simple, awesomely simple, that’s creativity.”

Challenging yourself to get creative by making simple yet impactful apps will help you grow as a developer. With KaiOS, you’ll have a place to show off your hard work.

Sign up for a Developer Portal account to get started. We can’t wait to see your app in the KaiStore!

Developer community

5 reasons developing mobile applications is easier on KaiOS

We know that developing web apps is cheaper, takes less time, and is more effective than building native apps, but we wanted to hear from developers about their experience building apps for KaiOS.

We chatted with Christian Waadt, Eli Shulga, Gabriel Rotaru, Victor Lee, and Ben Simms about why developing mobile applications for KaiOS is easier than for any other platform. Here’s what they said:

1. KaiOS is beginner-friendly

Knowledge of HTML, CSS, and JavaScript are all you need to start building apps for KaiOS. But if you don’t have these skills yet, there are free tutorials to help you learn.

Eli Shulga (Running Santa, Flying Egg, Socks Monster) taught himself how to code using free resources. “I just kind of became a game developer,” he says. “I found a tutorial and thought, ‘this could be fun.’”

Christian Waadt (K-Loan, wheelCal, Airship Combat 3D) also thinks anyone can learn. “It’s easy and pretty forgiving when your code is not super tidy in the beginning.”

2. Developing mobile apps for KaiOS is possible for small teams

You don’t need a large team to build KaiOS apps; most apps in the KaiStore were built by small teams or individual developers.

Victor Lee’s team (Treasure of Pirates, Kibi Cross) didn’t have the time and energy to invest in large projects, so they chose to invest their limited resources where they could have the biggest impact.

“We’d heard about KaiOS and smart feature phones, about how they have small screens and limited performance. We figured that these limitations would help us create games”, Victor says.

Most KaiOS developers have full-time jobs and work on KaiOS in their free time. Ben Simms (Boom Boom Fishing) works on KaiOS apps during his one-hour commute.

3. KaiOS developers get personalized feedback and support

Independent developers thrive on KaiOS because the developer support team is with them every step of the way. When you contact developer support via email or Discord, you can expect a response within 24-48 hours from an actual human.

“It’s good to know that there are real people working for KaiOS,” Christian says. “When you have a question, someone from the team, not a machine, replies.”

Personalized feedback kept Gabriel Rotaru (Guess the Logo, Hangman, Sliding Puzzle, and Trivia Challenge) going when, as a beginner, he felt like giving up.

“Fortunately, a KaiOS team member, Asis, reached out. With his help, I ended up building a trivia quiz app…It was enough to motivate me to build more,” he says.

4. KaiOS is invested in your success

Developers are essential to the KaiOS ecosystem. That’s why KaiOS supports them in building, launching, and marketing their apps:

  • The KaiOS Developer Portal is free and is easy to use, even for absolute beginners, and includes a simulator, a design guide, and WebIDE tools for debugging.
  • The developer support team is always available to help.
  • We feature developers on the KaiOS blog and promote their apps on social media.

5. KaiOS offers a less competitive environment for developers

Google Play and the App Store have millions of apps—2.56 million and 1.85 million, respectively, as of Q1 of 2020.

Reaching users in these crowded marketplaces is hard. “Without a huge marketing budget, your creation goes unnoticed,” says Christian. “If I publish a game [in Apple’s App store], it’s visible for about five minutes,” adds Ben.

Eli paid to promote his game Running Santa in the App Store, but it only got a few hundred downloads. In the KaiStore, it was downloaded 11,000 times without any paid promotion.

Victor’s app also had a higher engagement on KaiOS. In less than three months, KibiCross received six million impressions and 13,000 ad clicks.

Start developing mobile applications for KaiOS today

When we asked these developers what advice they would give anyone thinking about developing for KaiOS, they all said essentially the same thing: just do it.

“It might seem overwhelming at first, but don’t hesitate to contact the KaiOS team, because they’re really friendly and helpful,” says Gabriel.

“You really have personal access to the KaiOS team,” adds Eli. He recommends starting small so you can get your app into people’s hands and improve from there.

Ready to get started? Sign up for a free account in our developer portal.

Developer community

Why developing for a dumb phone is a smart decision

Dumb phones—candy bar and flip phone style mobile devices—aren’t as dumb as you may think. On the outside, they may appear pretty basic. However, newer dumb phones can do so much more than run games such as Snake. These improved devices—also known as smart feature phones—can connect to Wi-Fi; access 4G networks; run apps such as WhatsApp, YouTube, and Facebook, and come with Google Assistant.

As upgraded versions of dumb phones hit emerging markets at prices as low as $11 USD, they’re giving developers like you the unique opportunity to reach millions of consumers who are getting online for the first time.

Developing apps for dumb phones is simple

More evolved dumb phones run either web apps or progressive web apps (PWAs), their more advanced version. Development for either version is accessible to beginners.

Experienced native app developers and programmers can also easily adapt to web app development. Web programmers are at an advantage since apps for smart feature phones are built with HTML and JavaScript.

(Check out these free resources made for experienced programmers who want to adapt their skills and for beginners who want to give web apps a try.)

“I went from not knowing anything to putting a site together in a week. I don’t think there’s that type of parity for iOS. Much lower barrier of entry. I’m self-taught! ” — Alec Plummer, PWA developer

Web apps are easy to promote and maintain

When you submit an app to a native store, it quickly gets lost among millions of competing products. Unless you’re able to pay to promote your app and spend time creating and resubmitting updated versions of it, consumers may never discover what you’ve created.

“For me, it’s really important to be able to deliver an idea into people’s hands and see them play — that’s amazing. In other stores, it won’t reach many people. It will reach maybe two, and you’ll be one of them.” — Eli Shulga, KaiOS app developer

Getting your web app in front of consumers is simpler because it will be discoverable via an internet search on any mobile phone with a web browser. Sharing is straightforward as well; users can send a link to a web app just like they would with a website.

All you have to do to update a hosted web app is to adjust the codebase. Users automatically see the most recent version of your web app each time they access it. There is no delay like there is for native apps, whose updates are stalled days or weeks after being submitted to the app store. Not only can users begin using the latest version immediately, but you also don’t have to maintain an old version.

“The nice thing about a web app is that you don’t have to support a previous version of it, because it doesn’t exist anymore. With a native app, you have to support old versions because people won’t update.” — Nathan Hillyer, Developer, Boeing

Even packaged apps are easier to update on KaiOS phones. Just submit your new code to the KaiOS team, who will review and publish it within 48 hours in the KaiStore, where users go to find both hosted and packaged apps. If our team has any questions or feedback, they will work with you directly to resolve the issues.

By comparison, if your native app is rejected by Apple or Google Play, you’ll have a hard time figuring out why. The former requires an appeal process, while the latter prefers to let their bots reply to your questions.

Dumb phones are rising in popularity and reaching wider audiences

Based on sales numbers for dumb phones in recent years, more than a billion additional devices are projected to sell by 2021.

Sales for smart feature phones (internet-enabled dumb phones) are increasing, too—particularly in emerging markets such as Africa, the Middle East, and India. The KaiOS-powered JioPhones are among the top sellers, making KaiOS more widely used in India than iOS.

Low-price devices make mobile internet accessible to consumers who cannot afford expensive smartphones. For developers, this means gaining access to first-time internet users in previously untapped markets across the globe.

Because they are easier to use than smartphones, cater to people with lower digital-literacy levels, and offer an affordable way to get online, smart feature phones are ideal for those new to the internet. Web app developers have a rare opportunity to engage these millions of eager consumers.

Web apps don’t need to be overly complex to be impactful. Simple apps such as Period Tracker, Offline Dictionary, and World Radio are popular in the KaiStore because they address a specific need for users in emerging markets.

Now is the time to start developing for dumb phones

Smart feature phones make smartphone-like capabilities available on simpler hardware. By delivering mobile internet and apps through a more affordable medium, KaiOS devices are advancing digital inclusion around the world.

With the low barrier of entry for developers and the potential to reach such large audiences, the question isn’t why should you develop for dumb phones. It’s why wouldn’t you?

Get started by checking out the KaiOS Developer Portal, which provides free resources and direct access to the KaiOS developer support team.

Developer community

How to convert Android apps to KaiOS

Developers ask us all the time whether it’s possible to convert Android apps to KaiOS.

If it’s a web application built with JavaScript and web technologies, the answer is yes – and it’s actually pretty simple.

If it’s a native Android app built with Java, though, then porting is a bit trickier, and we recommend starting a new web application project in KaiOS.

In this post, we’ll share tips to help you get started, including how to ensure your apps run smoothly in smart feature phones.

Converting web apps to KaiOS

To migrate your web-based app to KaiOS, follow the instructions in the Getting Started section of our Developer Portal.

If you run into any trouble, contact and a KaiOS developer will get back to you shortly.

Converting native Android apps to KaiOS

Converting a native Android app into a web app isn’t possible.

You could try using the Google Web Toolkit to translate your Java code to JavaScript, but we can’t guarantee it will work.

Instead, we recommend starting a new web application project using the resources on our Developer Portal.

Don’t worry, you won’t have to start from scratch. You can keep the architecture of your original app and reuse assets such as icons, images, and audio files.

Things to keep in mind when converting Android apps to KaiOS

  1. Smart feature phones are non-touch devices. Redesigning your Android app for smart feature phones is all about transferring touchable elements to physical keys.
    For tips on how to do this while still providing a good experience for users, check out Optimizing Smartphone Apps for Smart Feature Phones.
  2. Smart feature phones have small screens. Use the devtools in your browser to see how your app performs in 320×240 screen sizes.
  3. Smart feature phones are low-memory devices. Keep your app light (file size under 15MB) to ensure users connecting in 2G and 3G networks, or via pay-by-the-byte plans, can download it. The average KaiOS app file size is around 2MB.

Get help from a KaiOS Certified Partner

Look out for this certification badge, provided to all certified KaiOS partners.

Need a hand migrating your Android app to KaiOS?

Certified Partners are developers and studios with experience developing for KaiOS and availability to work on KaiOS outsourcing projects.
If you’d like help converting your Android app to KaiOS, contact us at and we’ll connect you with a certified partner.

Developer community

Why it’s time to switch to web app development (Hint: It’s cheaper, faster, and has a wider reach)

Many developers shy away from web app development because they believe native apps have superior performance and are their best shot at reaching a large audience.

However, modern web apps can be released on any mobile device with a browser, which means they’re available to both smartphone and feature phone users.

Focusing only on native app development means missing out on millions of users around the world who are priced out of the smartphone market. Web app development not only provides access to a larger and more diverse audience but also allows you to go from idea to completed app faster and easier.

Web apps and their slightly more advanced counterparts, progressive web apps (PWAs), are an overlooked opportunity for developers. Here’s why it’s time to get on board.

Coding for web app development is simple and efficient

Web app development involves less complicated coding languages and shorter development timelines. And because web apps work across platforms, developers only need to test code once. Companies maintaining native apps need to invest in two sets of teams for the Play Store and App Store, thus a higher cost of R&D.

KaiOS app developer Eli Shulga “went from zero to submitted in four days” when developing a game for the KaiStore. His first game for a native platform took him nearly six months from start to finish.

Updating web apps on the KaiStore is quick and easy as well. If the web app is hosted, any changes to the back-end will force an automatic update. For packaged apps in the KaiStore, developers can simply submit the updated files, and the update will be live within 48 working hours.

For native platforms, you’ll have to go back through each platform’s separate app submission process. If your app is rejected, you’re likely to receive a generic response, sometimes from a bot instead of a human.

Whether you’re a beginner developer or just someone who wants to get their app onto devices quickly, web app development provides an excellent avenue.

“PWAs are a great option for beginners and independent developers. It’s so much easier to take an idea, build it, and deploy to all platforms.” — Alec Plummer, PWA developer

KaiOS provides free development resources such as the OS simulator.

Thanks to the simpler coding languages (HTML and JavaScript) and the variety of free resources available to improve your coding skills, web app development is extremely accessible.

Conversion rates are higher

Big companies, like Pinterest, Tinder, and Starbucks, have already seen the value of offering web versions of their apps. Several studies show that PWAs often lead to increased conversion rates.

52% average increase in conversion rates

Web apps have an SEO advantage because they are discoverable through an internet search. Once discovered, the apps can be installed on the device’s home screen in just one click, likely contributing to the average 52% increase in conversion rates.

Downloading native apps eats up data, which is a serious deterrent for data-conscious consumers. In fact, many users look for alternatives to downloading native apps, such as using file-sharing apps or “rogue” app stores which are detrimental to their internet security and user experience. Web apps and PWAs give users a better alternative.

Jeremy Doutte, co-CEO for Nigerian online marketplace Jumia, said that switching to a PWA made a big difference with customers: “We’re closer to our users with web push because it’s a more personal way to communicate with them. Customers aren’t willing to download our [native] apps, as they dread the impact on their data bills.”

This is also a major selling point for consumers in emerging markets where network coverage is limited.

“For intermittent internet access, PWAs are better. I don’t have to spend 40MBs on downloading an app. If you’re on a limited bandwidth, downloading an app will eat up your data and maybe you have to wait until next month to actually use it. With PWAs, you can add to the home screen and you don’t have to use much data to download it. This is great for developing countries.” — Alec Plummer, PWA developer

Web apps have the potential to reach a more diverse audience

Web app development not only allows you to enter a less competitive space but also helps you reach previously untapped markets through KaiOS

In more than half of low-and middle-income countries (LMICs), the price of an internet-enabled phone is greater than 20% of the average monthly income. This leaves mobile internet out of reach for millions of consumers in these markets.

“I think the web has a much broader reach. Much more diverse, maybe even cultural . . . almost everyone has internet access in the U.S. [In LMICs], if people don’t have access to smartphones, native apps won’t reach them. If the goal is to reach more people, web apps are the way to go.” — Alec Plummer, PWA developer

Web app development helps you reach a wider and more diverse user base because web apps are accessible on affordable smart feature phones. Consider this: in 2016 the average smartphone cost US$282. KaiOS sells smart feature phones for as low as US$11.

Developing apps for smart feature phones gives you a better chance of putting your content into the hands of the newly connected — an audience that would be difficult to reach through native platforms.

KaiOS developer account fees are $0

The Apple App Store bills developers $99 per year for an account, and Google Play charges a one-time $25 fee.

KaiOS removes these financial barriers by offering free developer accounts. Developers can learn to build apps for KaiOS with free resources and then release a packaged web app or a hosted app to the users through the KaiStore.

With KaiOS, developers get the added benefit of free personalized feedback. If you send an email to developer support, you will receive a response directly from our engineering team. When submitting to native platforms, your app submission could be rejected, and you’ll have to waste valuable time trying to figure out why. The KaiOS team provides complimentary support throughout the process of app submission and up until the app goes live. Developers also receive detailed feedback and insights on any submitted apps.

Native app developers: It’s time to try web app development

With web technologies continuing to improve, developers have begun to take note of this previously overlooked opportunity. Thanks to advancements in web app development, web apps and PWAs can provide a more native app-like experience while requiring less time, money, and effort from developers.

This is your chance to get your content in front of millions of users, many of whom will be going online for the very first time. Web app development is the future for mobile internet. Will you be a part of it?

Visit the KaiOS developer portal to get started! →

Developer community

An interview with KaiOS developer: Eli Shulga

Eli Shulga of Shugo Studios is a professional developer based in Tel Aviv, Israel, who has released mobile apps across multiple platforms. In the last three months, Eli published three games in the KaiStore: Running Santa, Flying Egg, and Socks Monster. His Twitter is full of drawings and videos showing the development process for his unique sketch-style games. We chatted with Eli to learn more about his experience and future plans.

How did you start developing for KaiOS?

Justine, the Strategic Partners Manager at KaiOS, reached out to me. I have a small studio, just one man, so that means a lot. No partnership manager would contact me from other platforms! That’s one of the things I like about KaiOS and what made me want to develop for them.

What else made you want to develop for KaiOS?

First, I really loved the idea of doing something small and simple with my animation and my style. And it’s very fast from idea to production. The second reason was KaiOS’s cause — to bring internet access to people who have never had access.

Tell us about your experience developing your first app for KaiOS.

Initially, I told Justine I didn’t have time, but I decided to test things out. I wanted to see, as an artist, how I could produce a really small scope game — a real production-ready game with all the art and animation — in a really short time. In December 2019, I created Running Santa. I went from zero to submitted in four days.

How does that timeline compare to your experience developing for other platforms?

[Laughs] Well, getting my first game into both stores (Apple and Google Play) took almost six months. The second game was Running Santa. I liked the reaction it got on KaiOS, so I decided to make it for Apple and Google Play. It’s a really good comparison actually because it’s the same game, but it took me two weeks to change things and release it on other platforms.

Two weeks is better than six months! How did you prepare Running Santa for native platforms?

I had to add in a game menu and a bunch of other stuff for touchscreens – start menu buttons, game settings menu, sound and music controls – all of those things had to be drawn and coded. I do frame-by-frame animation, so I had to draw all of Santa’s movements separately. I also had some issues getting local storage to save the player’s high score.

I use Cordova to wrap Phaser* into Android and iOS apps. Building the wrapping process takes time but once you have the template you can apply it to future web app projects.

* Phaser is a mobile and desktop HTML game framework. It can be used to “wrap” web apps into native mobile applications.

Was the user response different on other platforms?

I’ve had the most success with KaiOS. Running Santa has over 11,000 downloads from the KaiStore, and I didn’t put any money into promotion. For the Apple Store, I did a paid promotion and got maybe a few hundred downloads.

How was your experience developing an app for KaiOS compared to other app stores?

With KaiOS, you really have personal access to the dev team. You just email them, and they’ll help you. Apple has a lot of guidelines and rules you have to review. You don’t talk to a human unless your app is rejected, and you file an appeal. With Google, bots are answering questions.

Getting a game app on KaiOS is simpler. The development time is shorter, and all you really need is a computer and an internet connection.

For me, it’s really important to be able to deliver an idea into people’s hands and see them play — that’s amazing. In other stores, even if you put it into the app stores, it won’t reach many people. It will reach maybe two, and you’ll be one of them.

Which of your apps is the most popular?

By total downloads, Running Santa, but Socks Monster was just released and might overtake it. KaiOS does a lot of promotion and push for you. The big stores, they don’t really help you. It’s a big plus for KaiOS — they are very supportive, and that means a lot.

I also shared a lot of the development process for Running Santa and Socks Monster on Twitter as part of the #100DaysofGameDev challenge – a Twitter hashtag game developers use to check in with other developers and share the progress of the games they are creating.

I share my process and what I know because giving back is fun. I take a lot of things I learned from the net and YouTube. I can’t point to where I learned something specific — it’s a bit from her, a bit from him — you are building yourself. Saturating yourself with something when you want to learn it, that’s a very important part of the learning process.

What made you want to participate in the #100DaysofGameDev challenge?

Part of it was to share what I know, but it was also for accountability. In the beginning, it was just for fun, but then it became a commitment. I create for myself, but the challenge was at the back of my mind. It made me go the extra mile and do a bit more.

Now that Socks Monster is live, are you working on anything else?

Of course! I just attended the Global Game Jam here in Tel Aviv and started working on a sort of follow-up game to Socks Monster called Washy. It’s a game about a broken washing machine. I’m also working on a game called Easy Dude.

What advice would you give aspiring game developers?

Just do it! Make a game as simple as possible the first time, and the only goal should be to finish it.

Other than art and app development, what do you do for fun?

I make time for friends and do a lot of sports, like Olympic kayaking. I participate in some local competitions in Israel.

You can follow Eli on Twitter, Instagram, YouTube, and Itch.

Interested in building your own KaiOS apps? Head on over to the Developer Portal to get started, or get in touch with Asis at for any questions you might have.

Don’t forget to subscribe to our “Developer Updates” to get the latest news on development in the KaiStore.

Developer community

Why Koji is the perfect resource for beginner KaiOS app creators

As of September 2019, Google Play and Apple had 2.4 million and 1.8 million apps to choose from, respectively. As app stores grow, so does the competition for developers. Whether you are just getting started as an app developer or are an experienced professional looking for a way to stand out – developing content for KaiOS is a great opportunity.

We continue to bring smart feature phones and mobile connectivity to millions of people in underserved markets around the world. Our new partnership with Koji makes creating content for those consumers simple, regardless of where you are from or your experience level.

What is Koji?

Koji is a development platform available in six languages on which anyone, including non-technical beginners, can create apps. App templates developed by professionals can be “remixed” — including a variety of design elements such as images, colors, and sounds — by others without touching a single piece of code.

The unique remix capability, which can be done using an internet-connected mobile device in under 30 minutes, makes customizing apps quick, easy, and possible for those without access to a computer. The Koji platform also has an integrated live preview window where you can see the results of your app, which reduces the dependency on testing on real devices during the development phase and speeds up the development process.

KaiOS and Koji are a perfect combination. While Koji aims to empower people around the world to develop apps, they recognize that many underserved areas lack the internet connectivity and devices required to do so. That’s where KaiOS comes in, making devices and mobile internet affordable and accessible. Together, KaiOS and Koji provide a way for developers, beginner or advanced, to share their content with emerging markets.

What does the partnership between KaiOS and Koji mean for developers?

This partnership paves the way for developers by providing a variety of valuable materials, resources, and support from both parties.

Resources for beginners

Remixing apps allows even absolute beginners (or “Makers” as Koji calls them) to get started with app development. Take the game app created with Koji by Jenise Spiteri, a professional snowboarder and YouTube vlogger. Spiteri used a photo of her face and recorded her own reaction phrases like “score!” and “radical!” to personalize the game for her audience.

“I thought it was very simple,” Spiteri said. “I didn’t really come into any problems, the platform itself and Visual Customization Controls (VCCs) for remixing a game were all super user-friendly. It’s like game developing for dummies!”

The vlogger leveraged her game to collect emails from her fans and drove engagement by awarding prizes to high scores.

Beginners like Spiteri enjoy both the ease and the speed of remixing apps. On average, it takes only 10-30 minutes to remix an app on the Koji platform. Makers simply pick an app template and use Koji to change VCCs to change colors, images, sounds, and game settings all without code.

Resources for experienced developers

While professional developers are welcome to remix apps, they can also create app templates by importing their JavaScript code into a Koji Project. The purpose of app templates is to allow Makers to easily swap out design elements, so it’s important for developers to build their code to include a variety of customizable VCCs.

Koji developer Svarog1389 used a fruit-slicing game example to explain this process. In his step-by-step tutorial, he demonstrates how to code VCCs, such as fruit images, sound effects, game settings, etc. Thanks to this coding, a Maker could easily remix the fruit-slicing game into a water balloon-bursting game by simply swapping in balloons for the fruit images and water splash sounds for the slicing sound effects.

Experienced developers can quickly learn how to create app templates with the help of the free Koji for Developers guide.

Ongoing technical support

Whether you are remixing an app or creating a template, Koji and the KaiOS community offer ongoing support through a few different methods.

Documentation on Koji for Developers provides in-depth instructions for developing on the Koji platform. The Koji YouTube channel also features several tutorials made by Koji and their users, including 16-year-old Kumar Abhirup.

Abhirup created 10 apps in two months, eight of which are remixable templates. He encourages Makers and developers to appeal to international users by translating apps into different languages. His tutorial walks viewers through the process of changing the language and settings of a game with the Koji remix function.

In addition to these tools, aspiring developers and Makers can receive live support via the Koji Discord chat. The Koji team and fellow developers are available through a variety of channels, including a KaiOS-specific channel where you can chat with KaiOS chief architect Fabrice and software engineer Billy.

Koji also frequently hosts webinars during which they provide live guidance and respond to questions from attendees. Be sure to keep an eye out for KaiOS-focused webinars to learn how to submit apps made via Koji to the KaiStore.

Marketing assistance

Once your app has been submitted, you can benefit from increased exposure through both KaiStore app promotion and the Koji blog.

KaiOS shows recent apps at the top of the KaiStore, so developers can get their newly added apps in front of KaiOS users right away. Featured apps are also highlighted on KaiOS social media channels, blog posts, and on the recommended tab within the KaiStore.

Koji provides additional marketing support by highlighting apps on their blog and in the press. Media exposure is incredibly valuable for developers. Features can lead to more app downloads, higher traffic to personal websites and YouTube channels, plus increases in social media followers.

Stronbol, a 15-year-old YouTube gamer, experienced this firsthand when he became Koji’s first Hispanic influencer.

Stronbol surprised his followers with Torre De Stronbol, a remixed version of the Koji classic game, Tower Stack. He then launched a contest that offered prizes to users who created games about him. The result was over 90 fan-created games.

Access to underserved markets

As affordable KaiOS-enabled smart feature phones enter emerging markets, millions of people are getting connected and using apps for the first time.

Devices running KaiOS are accessible in key markets such as Africa, Southeast Asia, the Middle East, and many Low and Middle Income Countries (LMICs). Developers who submit apps to the KaiStore can benefit from less competition compared to native app stores such as the Apple App Store or Google Play where apps can easily be buried among millions of others.

Developers who create content that appeals to audiences in emerging markets have an even greater chance of standing out. Luckily, Koji makes changing the language and even the text direction within any app simple. Language settings are set as VCCs that can be altered without any coding experience.

Monetization options

Professional and beginner developers have the chance to monetize apps hosted in the KaiStore after creating them with the Koji development platform.

  1. Monetization through Koji

Koji has enabled the opportunity for app template developers to get rewarded for their creations. Users can purchase Koji Pennies so that they can leave tips for developers. The Koji Pennies can then be cashed out for actual currency.
Professional developers also have the option to charge for extended help. If a less experienced developer requests additional guidance, professionals can charge hourly or project rates to provide it.

  1. Monetization through KaiOS

Both developers and Makers can develop apps with Koji and submit them to the KaiStore. Once their app is live in the store, they can earn money through in-app purchases and Kai’s advertisement solution, KaiAds.

Koji apps now available in the KaiStore

A few apps have already been created using Koji, such as MatchCard and JiTimer. They are now available to KaiOS users and to Koji developers who want to remix them. In fact, we have used the MatchCard app and remixed it again to create a Christmas Memory Card game! The remixing capabilities allows developers to quickly build and deploy apps for different themes.


It’s a memory game and the first app available in KaiStore using Koji – Play here


A straightforward, useful timer app – Play here

Christmas Memory Game

A Christmas-themed memory game which is remixed from MatchCard – Play here

It showcases the capability of Koji and how developers can easily create seasonal or themed games for different markets.

Start using Koji today to develop for KaiOS

All you need to get started with Koji app development is a mobile phone or a computer with internet access. Take a look at these app templates that work well on KaiOS devices. And check out this new tutorial video to learn how to create a KaiOS app using Koji.

Once you’ve created something you’re proud of, don’t forget to submit your app to the KaiStore. We can’t wait to see what you create.

Developer community

Something exciting is happening in Africa

Electric is the word that comes to mind when we think of the past weeks we spent connecting with the developer community in Africa.

We could feel it in the talks given by digital innovators at the African Developers Conference, in the questions people asked us during our workshops, in the conversations we had with developers and entrepreneurs: There’s momentum in the African digital landscape.

While we knew that Africa was ripe for digital innovation, we hadn’t had a chance to connect with the developer community there until recently, when we took part in a series of events we either organized or attended in mid-October. Through these events, we got to know some of the creative, enterprising people already shaping the region’s digital landscape, as well as the young talents that will take the revolution even further.

We met fifty or so of them of these young talents at Moringa School, a multi-disciplinary coding school in Nairobi, Kenya. Moringa provides technical and professional training to high-potential students to help them compete in a digital economy. In the workshop we gave them, we got them stoked about building KaiOS apps and gave them the resources to get started, including an introduction to our developer portal.

Our second stop was the Africa Digital Media Institute, also in Nairobi, where we showed yet another group of students how coding for KaiOS is easy, profitable, and potentially transformative.

Next, we touched base with the AGD (Africa Game Developers) – Africa’s largest gaming community – in Kenya. It’s no secret that Kenya’s video games industry is soaring – the BBC recently reported that the video games market in the country, worth over $50m in 2016, was expected to double by 2021 – and the talks we had with some of the key players in the community just confirmed that.

For them, creating interactive content for and about Africa is about empowering people in the region. We are 100% behind that. As champions of locally meaningful apps, we can’t wait to see what Kenya’s gaming talents create for KaiOS.

To Kenya’s video game creators, producing interactive content for and about Africa is about more than entertaining. It’s about empowering people. We believe that too, and we can’t wait to see what they create for KaiOS.

We ended our tour with an appearance at AfriDevCon, in Ethiopia, where we welcomed KaiOS enthusiasts in our very own booth and ran, yes, another two workshops. It was an exhausting but inspiring few days. We came back to our offices more inspired than ever.

If you have creative, inspiring content that would like to run on our platform, please contact me via