You can remove the Hangouts app, or use another messaging app.
Sign out of Hangouts and use another app
If Hangouts is preinstalled on your device, you can't delete the app. If you don't want to use Hangouts, sign out and use another messaging app.
- Open the Hangouts app .
- At the top left, tap Menu .
- Tap Settings.
- Tap your Google Account.
- Scroll to the bottom and tap Sign out.