As for React Native for a beginner I found really annoying having two official CLIs - CRNA and React-native CLI, also the whole ‘compiling’ on Expo thing is really a nonsense to me. RN claims to offer faster developing yet almost nothing works out of hand, there is always a need for little tweaks or hacks.
Tbh, I used Ionic 1 A LOT, made even some apps with it, then it came Ionic 2 and transition they offered was really poor, also the idea of running an app in a webview(when you come from native) is very mind boggling.
So what are you going to suggest me Core or Angular?
Most definitely I am going to write one bigger app in Nativescript, almost got API ready for it. How complicated are REST calls and JSON parsing, I guess it as simple as in Angular ?
Thank you for the great answer