TL;DR: Use the rn-geolocation npm package. After you install it, install Google Repository and Google Play Services dependency. Add the plugin to your Android build by changing your settings.gradle and android/app/build.gradle and add the package to your MainActivity.java.
For the past few days I have been developping a React Native app for Android. One of the things I needed for my app was geolocation. I started by trying navigator.geolocation just to figure out that the Geo Location module is a Missing Module in React Native for Android. Since that was not an option, I set out looking for answers:
The ones I found depended on external libraries, so in the end I ended up creating my own rn-geolocation native module for Android. I have to thank Corentin Smith for sharing his Java code with me. I ended up using most of it for my package.
Originally published at blog.bamlab.fr on November 11, 2015.