Android is all about syncing and sharing with your social networks accounts. Check which Android app is connected to Google+ account and what the permissions are. Do as follows:
1. Go to your App Drawer and open "Google Settings". (This app is automatically installed to your device when you first open Google Play)
2. Tap "Apps with Google+ Sign in"
3. List of connected apps are shown based on the chosen account (You may use the menu bar to change the account)
4. To see the permissions for each app and control who can see your activities, tap the Application name
5. Tap "Activities visible via Google to" to change who in your circles can follow your activities