Kartoffel is a framework, composed of different components. On one hand it allows developers to create touch based apps for microcontrollers with ease, and users to download them, wire them if needed, and install them in their microcontrollers. This framework is Open Source, meaning anybody can take a look at the source code and do almost whatever they want with it. It is also free, you don't have to pay to use it. We also don't track you.