I would like to ask about creating cxxreact type modules, as you have done with your OpenGL module. Was it difficult to integrate, and would you recommend this approach for integrating a cross-platform C++ library into React Native?

You can take a look at the React Native docs... I've personally used it to build a couple of apps now, and I actually would not agree its the easier method. At least in one case (where part of the app is in C++) I think it would have taken me less time to use Swift and make it iOS only, but a lot more time to code up both native iOS and Android versions separately.

This is not true. React Native can be as native as you need it to be. You just need to find the right libraries to use, and if necessary write native modules yourself. This of course requires some familiarity with the native platform (i.e. Android and Java in this case). The upshot of doing it this way, is that porting it to iOS you would have 80% or more of the work already done :)

rust, I want to try building performant, stable audio apps without the dangers associated with C++

The first significant contribution was to the JUCE C++ framework, for some Android related additions to the project exporter. It felt great to have contributed to such an amazing framework. I've since contributed a few more patches to JUCE as well as to various React Native modules. Its a good feeling to be giving something back to the developer community.

I'm using RN for managing data and navigation and JUCE for audio and custom animated views. Working well so far, after ironing out configuration issues. I've settled on wix/react-native-navigation for my navigation, pure JS navigation is just too slow on an iPhone 4S. I started in Objective-C, then moved to Swift and finally settled on RN partly so that I can easily port it to Android. React Native and Redux make a lot of sense to me now.