What technology was used when writing instagrams for android?

Question

Android

In this question, I mean ui Widgets are clearly not systemic, and indeed not material design at all. Reminds me of cupertino. This is where it got interesting.

Answer 1

As far as I know this is ReactNative
Here you can see facebook.github.io/react-native
Apps on ReactNative facebook.github.io/react-native/showcase.html