Is KaiOS truly an emerging OS?

Before discussing the KaiOS mobile operating system groundbreaking entrance, Let’s focus on the first question that comes in mind.

What is KaiOS?

KaiOS mobile operating system which is web-based enables a new category of smart feature phones. It is the successor of Firefox OS but with more features and robust in nature.

So let’s talk about some cool features.

Support for 4G LTE E, VoLTE, GPS, Wifi.

HTML5-based apps and longer battery life.

Less memory and energy consumption.

And still, there are many more features that might need an entire blog dedicated to it. So moving on…

You might think what so cool about this OS? when all these features are already there in our smartphones. Then what makes it different than others?
The price point of KaiOS mobile operating system, because all these features you can have in featured phones at an affordable price. Plus it comes with, Kaios Store with some inbuilt apps like Youtube, Twitter, Facebook. And it takes about 256 MB to run an app.

So next why anyone will choose Kaios out of other ravaging Mobile OS’s out there?

Why KaiOS?

If we look into the world there are still vast groups of people locked out of the digital revolution; some of them don’t have even basic internet access, So for these people, KaiOS developer is the best choice because they can connect, evolve and learn using this technology as it provides many features like smartphones.

Fun Fact: Recently Google has invested $22Million to develop KaiOS.

Due to these upheld thinking, even Google is also ready to invest.

So let’s move onto the fun stuff

Which technology have they used?

KaiOS developing apps are based on web technologies – HTML, CSS, and JavaScript and are run by Gecko runtime.

Javascript is rendered using  SpiderMonkey which is Mozilla's JavaScript engine written in C and C++. It is used in various Mozilla products, including Firefox, and is available under the MPL2.

So after knowing the technology they have used, we can dive into the question of how can we make apps for the kaios? 

How to get started?

How KaiOS mobile operating system actually works internally.

So in a short note

It has a front end called Gaia which contains application and shared js libraries ex-home screen lock screen and inbuilt apps are Gaia

Next comes Gecko Layer which is a presentation or web engine layer which ensures that the web API works fine with all the devices. It provides the connection between frontend and underlying hardware

And finally Gonk Layer Low-level operating system of the platform It’s a very simple Linux distribution which does all the underlying things to contact with hardware level

If you want to know more about the architecture, you can refer to this link 

And next

What should we know in order to build apps prerequisites?

The basic web development technology like HTML5, CSS, and javascript that’s all we need. If you have an even basic understanding of these technologies then you are good to go.

So the next step is to build apps so that Mozilla has provided a platform to build on ( Web IDE).

You can find this IDE in firefox v59 or Waterfox Classic Edition or older versions of withering FF/WFox for KaiOS implementations, to download these versions, you can get them through Mozilla FTP. Or if you can’t find there then there is a trick download Waterfox.

And to start Web IDE press (shift +f8)


Install a simulator to run your apps on if you don’t have Kaios supported phone. You can even get a KaiOS featured phone simulator with keypads but it’s only supported in Debian/Ubuntu or any of its derivatives. For more information and to download visit
And finally, you are ready to build your first app. You can build basic apps and can use the underlying inbuilt Web API in order to connect with hardware. To know how you can visit
If you want to know some more stuff you can freely visit
You can check out the following link 

to see how I implemented the above-mentioned steps and build basic weather forecasting using HTML, CSS, and angular. Here are some screenshots below.


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Written By: Pritesh Chowta ( Trainee Software Engineer in Pacewisdom)