As KaiOS heads into emerging markets like Africa, Latin America, and Southeast Asia, we are on the lookout for mobile apps to add to our KaiStore. In particular, we’re interested in those designed to improve the lives of people within these markets, such as educational apps for schoolchildren, banking and financial services apps designed to bolster financial inclusion, and agricultural apps that help farmers gather real-time data.

The KaiStore — available online through phones running the KaiOS operating system — functions much like other app stores but provides opportunities for developers with ambitions of reaching a wider audience as KaiOS is available in more than 100 countries.

Developing native apps to run on other app stores requires extensive resources, especially when you are targeting both Android and iOS. On the other hand, you can easily port web-based apps developed for KaiOS to multiple platforms because the operating system is based on web technologies.

Why develop for KaiOS?

Having already surpassed Apple iOS in India to become the second most-used mobile operating system in the country, KaiOS is quickly becoming a powerhouse. The technology is built to meet the needs of emerging markets by offering a low-cost alternative to touchscreen devices. KaiOS growing fast in such areas as Africa and Latin America.

Currently, KaiOS runs on over 100 million phones worldwide and is on track to run on 150 million by the end of 2019. As of 2017, the Google Play store had 724,000 mobile app developers and the Apple store had 494,000. With so many developers in the same space, it’s difficult to stand out against the competition. Developers who submit apps to the KaiStore early on can enjoy a less competitive environment and still be able to reach millions of users around the world. As such, successful KaiOS apps have the potential to be very lucrative. Plus, they’re easier to build than their native counterparts from Google and Apple.

With KaiOS, developers use coding languages like HTML, CSS, and JavaScript to build web-based apps. Even those who are brand new to app development can get up-to-speed quickly and have just as much opportunity to design successful mobile apps as experienced native app developers. Skilled developers, too, have opportunities to reach new consumers by transitioning existing native apps to web-based apps.
Ready to get started with KaiOS app development? The following resources will help you design apps for the KaiStore.

Official resource for developing for the KaiOS operating system

Our developer portal for KaiOS operating system app development covers topics such as core development, design guidelines, debugging, and submitting to the KaiStore. Below are three of its key sections:


Use the simulator to mimic running your web app on a mobile device. Here, developers can access instructions for ENV setup and building their first app.

Design guide

To attract users and keep them engaged with your app, designing specifically for the KaiOS operating system is key. Learn how to capture and maintain users’ attention through creative motion, clear typeface, and pleasing imagery by experimenting with the KaiOS UI Design Resource Sketch files. Navigate your app as a user would, and design with the user experience in mind.

Run and debug

Once apps are ready for testing, developers can use WebIDE tools to identify issues and assess app performance and memory before launch and over time. Learn how to examine and modify HTML and CSS, track down JavaScript bugs, preview the effects of code changes, and more.

Design at Kai medium UX series

In addition to the Developer Portal, we’ve also put together a UX Design series. Here, developers can check out behind-the-scenes stories written by the KaiOS UX Design Team. Developers who are new to smart feature phone app design can get advice on how to optimize over-scroll effects, design for smaller screens, arrange softkeys, etc.

Resources for learning HTML5

KaiOS apps run on web technologies, so studying HTML5 mobile app development is essential. When designed properly, HTML5 mobile apps functioning on the KaiOS light operating system will perform just as well the native app version. In fact, HTML5 apps can also be packaged to be released in native app stores without users experiencing a noticeable difference in performance.


Whether you are just getting started with HTML5 or refreshing your skills, W3Schools is an excellent resource. Like classes at a traditional school, their lessons include tutorials, study guides, and quizzes to test your comprehension.

Josh Morony

Josh Morony regularly posts free HTML5 mobile tutorials. He also has several articles worth reading on HTML5 such as 7 Lessons from 3 Years of HTML5 Mobile Application Development, 5 Things Beginner HTML5 Mobile Developers Should Know, and Top 10 Tools for HTML5 Mobile App Developers.

HTML5 programming tutoriaL VIDEO

If you learn best through videos, check out this 25-minute tutorial to watch the process of designing a basic HTML5 app from start to finish.

HTML5 Game App Templates

This collection of 20 game templates is perfect for hands-on learners who want to explore the source code of different apps. This is a great way for developers to get inspiration for their own apps.

Additional resources for developing KaiOS apps

Once you’ve gone through the official KaiOS developer resources and brushed up on HTML5, check out these additional resources.

MDN Web Docs

KaiOS was originally forked from B2G (Boot to Gecko), which is a successor of Firefox OS. For that reason, it’s helpful to get familiar with the basics of the discontinued Firefox OS as KaiOS still shares many of the same development principles.

To build a foundational understanding of the operating system, beginners can read the MDN Web Doc’s step-by-step guide.

Porting Web Apps to KaiOS

Existing web app developers who want to develop for KaiOS can refer to this quick guide. It provides a simple process for porting existing web apps to the KaiOS operating system.

Now is the time to develop for KaiOS

KaiOS expects to run on 50 million additional phones before the end of 2019 and will continue to expand in the coming years. Developers who create mobile apps for KaiOS now will get first access to new consumers as KaiOS enters previously untapped markets. And your apps will be in great company — we’ve already worked with the likes of WhatsApp, Facebook, Twitter, Google Assistant, YouTube and more. Bring your creative ideas to areas of the world that went from having limited internet access to having an exciting world of apps to explore on affordable mobile phones.

Get started with KaiOS mobile app development by visiting our developer portal. We can’t wait to see what you create!