I am trying to implement firebase in android project but always getting:
Google Play services out of date.
Requires 9877000 but found 9683480
apply plugin: 'com.google.gms.google-services'
Google Play Services in an emulator will not be auto-updated. This means that you will need to create a new emulator image to get the 9.8 version of Google Play Services. If you create an image with Google APIs after installing the latest SDK and support libraries, it should have the latest Google Play Services too.
If you deploy to a physical device, it'll likely already have the latest version.