Most up to date Android apps are currently targeting API level 24 or 25, so it makes it very difficult if not impossible to integrate React Native into an existing app considering that API level 23 seems to be the highest that is supported by React Native.
When using the latest version of React Native (0.45), targeting API level 25, and using the 25.x.x versions of the support libraries, we see the following error:
IllegalAccessError: Method 'void android.support.v4.net.ConnectivityManagerCompat.()' is inaccessible to class 'com.facebook.react.modules.netinfo.NetInfoModule'
It seems as though it was introduced even further back, in version 23.2.0 of the support libraries. There is conversation about the issue here - https://github.com/facebook/react-native/issues/6152.
Not sure what other issues might pop up but this update would be great for established Android apps that use the latest features of the platform to start adopting React Native.