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[calclavia]

There are several things I encountered when installing this native module that I would've appreciated if it was documented. Feel free to add these to the README.

1. For iOS, simply placing the generated JSON file from Google into the iOS directory is insufficient. http://stackoverflow.com/questions/31294380/unable-to-find-googleservice-info-plist-while-trying-to-integrate-google-sign
2. For Android, applying the Google play services Gradle plugin should've been done at the bottom of the Gradle file.
3. For Android, I had to add new FIRAnalyticsPackage() in the getPackages() method in MainApplication.java.

[KendraTang]

Just note that for point 3, you would have to add
import com.evollu.react.fa.FIRAnalyticsPackage;
in MainApplication.java too.

[sibelius]

@calclavia could u please send a PR to fix this?