We are using SQLite on React Native with the JSI without writing a java or object C bridge. As a result, all operations are much faster and almost all of them don't need to Promise callback.
I don't see any reason to use this over SQLite. We can do same thing on SQLite much faster way.
The primary use of MMKV seems to be a replacement for NSUserDefaults. I agree the SQLite is probably the best solution overall, but this could be a faster alternative to anyone just using NSUserDefaults
That is true but still MMKV due to its simplicity and small size is a very fast option over AsynStorage on both android and iOS. It has been used in the WeChat app used in China for datastorage.