Note: I'm a web dev that started in on mobile dev due to a few ideas I had. I am not an experienced mobile dev.
When I first started mobile development, I narrowed my choices to two: React Native and NativeScript.
NativeScript has a few features I like about it. First, you can choose Angular, Vue.js (supports Typescript), or vanilla JS.
NativeScript runs natively (mostly). And the team there suggest that NS may have certain features that would fare better over RN. That being said, NS wasn't a fun experience. NS requires two apps, one to connect to your project, the other to open your project. The live reloading didn't always work, and compiling became an issue for small things. While my experience was certainly a factor, the documentation didn't always cover my needs. Portions of the docs were old and outdated. Other portions vaguely covered topics.
So I tried out React Native. There's a great course at http://www.handlebarlabs.com/ that was recently updated. While I didn't start with that course, I ended up using the course to expand my knowledge on professionalism (standard folder structure, etc.) in RN.
The only downside I've had so far with RN is the debugger. The debugger is not always clear with errors.
Possibly my favorite part of React Native is navigation. It's fairly simple to setup and create a basic app with navigation. I only use React Navigation, but there are a few other choices out there. (That being said, I couldn't figure out navigating in NS. It would continually break on me, even with the templates.)
That being said, whatever framework or library you use, I'm hoping you enjoy it!
Want to correct me? Want to add something else? Feel free to drop a comment.