Valeriy Skachko planning his next app

A former teacher in Lugansk, Valeriy Skachko had to leave his home and his job when war broke out in eastern Ukraine. Four years later, he’s an accomplished freelance developer based in Ivano-Frankivsk. He built 21 apps on KaiOS just last year,  ranging from a period tracker to a talking hamster. He also runs, the largest and most popular website about KaiOS in the Russian language. Learn more about this KaiOS enthusiast and prolific app developer.

So, tell us how your story with KaiOS began.

In 2018, I read about the Nokia 8110 4G. That’s when I learned about KaiOS. I studied the system and fell in love with it. Hearing that KaiOS wanted to expand the capabilities of feature phones and modernize them inspired me. I decided to create apps to help KaiOS users take full advantage of their smart feature phones. I wanted to contribute to the KaiOS mission.

When did you start building on KaiOS?

I built my app in April that year (2018). There was very little documentation at that time, but I was determined to build at least one app, so I sent several emails to Support until they connected me with Harshdeep Vaghela, who helped me with the first steps in the development process (he still helps me a lot, so thanks, Harsh!) Nowadays, it’s much easier. There’s plenty of documentation on the Developer Portal and the support team replies much faster.

What do newbies most struggle with when starting to build on KaiOS?

The first problem is that, to create a KaiOS app, you need a KaiOS device. The simulator isn’t enough to fully test an app. The second problem is that most developers create apps for touchscreen devices, so they have a hard time rewiring their brains to build for non-touch devices. Third, you’re dealing with small screens, so you have to be mindful of that.

Any tips or advice you can share?

My advice is research, research, and research. You can find lots of info at MDN Web Docs (most docs for Firefox OS also work on KaiOS). Ask questions in forums like this one. And buy a KaiOS device.

Screenshot of Sun Compass, an app by Valeriy Skachko
Sun Compass, an app by Valeriy Skachko

You’ve built 23 apps so far. Are they similar in any way?

I see the phone as a means of communication and as an assistant in life, so I try to create apps that are useful. I’m not very interested in games, for example, although I would consider creating an intellectual one.

Which of your apps is the most popular? Which one are you most proud of?

My most successful apps are World Radio and Night Clock. The one I’m most proud of is World Radio – it has online radio stations from all over the world. I try to add new radio stations every week. Right now, it has stations from 37 different countries!

World Radio, one of Valeriy’s favorite apps
Voice Recorder, another one of Skachko’s creations

Cool. So how do you get ideas for apps? Do you already know what you’re building next?

I ask myself what I miss on a feature phone – then I go and build that. I also get ideas from comments made by users.

As for what I’d like to build next, I’d love to make Bluetooth chat, and more reference books, available. I’d also like to expand the functionalities of some of my existing apps (World Radio, for example).

Do you have a goal in mind, such as building 50 apps by the end of the year?

Not really. My goal isn’t to create as many apps as possible. I’d rather create one good app than build five bad ones in the same amount of time.

Besides KaiOS, what else are you into?

I love traveling with my wife and daughter. I try to visit one new country every year. Last year I was in Georgia; before that, I was in Israel; before that, Turkey, and so on.

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

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