To enable Google Fit API in an Android application, create or update a project at:
https://console.developers.google.com/flows/enableapi?apiid=fitness
To get the production OAuth 2.0 ID client, the certificate can be found with the command
keytool -exportcert -keystore /data/Projets/workspace/config/keystore/GMT_android_market.keystore -alias guenmattools -list -v
To get the debug OAuth 2.0 ID client, the certificate can be found with the command
keytool -exportcert -keystore /home/guenmat/.android/debug.keystore -list -v -alias androiddebugkey -storepass android -keypass android
The value from the line SHA1 must be used.