I was just going to mention Flutter. It’s a completely new and awesome UI framework, which can be used cross platform (mobile, web, embedded, desktop, gaming, you name it). It is already being used extensively for mobile (both iOS and Android) and for the Google Assistant. There are around half a million developers using Flutter monthly. And then there is its use in Fuchisa.

I expect that eventually this will be considered as important as Linux. Maybe even more, since poor user interfaces (especially on devices like TVs) are something that desperately needed fixing. Plus it is completely open source.