Dawn Chorus an app I worked on, which was featured on the iOS app store[1], was written completely in React Native.

Here are the App Store links:

iOS: https://itunes.apple.com/us/app/dawn-chorus/id1146931666?mt=...

Android: https://play.google.com/store/apps/details?id=com.dawnchorus...

We even open sourced it: https://github.com/CMP-Studio/DawnChorus

I believe it is an example of a high fidelity and quality React Native app on two platforms.

[1] https://rubennic.com/static/img/Dawn-Chorus.png