GoogleApiClient onConnected never called on Wearable device
Oh wow, the answer is embarrassingly simple. I missed the part where in onStart() you need to call mGoogleApiClient.connect().
You can call the connect and disconnect manually in the onStart and onStop lifecycle methods, or you can use the enableAutoManage feature.
mCredentialsApiClient = new GoogleApiClient.Builder(this) .addConnectionCallbacks(this) .enableAutoManage(this, this) .addApi(Auth.CREDENTIALS_API) .build();
Additionally, I noticed that if you try to do GoogleApiClient when user hasn't setup Google Play there can be a conflict connecting. (I just reset my device and that's what happened). So it's a good practice to test connection from GoogleApiClient using
mCredentialsApiClient = new GoogleApiClient.Builder(this) .addConnectionCallbacks(this) .addOnConnectionFailedListener(this)Or just check mCredentialsApiClient.isConnected() before peforming any task.