I recently purchased a new phone (OnePlus 8 - Black Friday deal for $250. Woot woot!). This morning, I found that the Gmail app was missing my old Google Hangouts and I didn’t see a ready way in settings to add it, yet I had access to my old Hangouts groups in Gmail on my old phone…
A couple of Google searches didn’t turn up anything either: just some very old and outdated instructions. It probably doesn’t help that Google has rebranded and changed the name of Google Hangouts multiple times over the years, first as Hangouts, then Google Chat, and now Spaces. It doesn’t help that Google itself doesn’t seem to keep this terminology distinct.
So here is how to add Google Hangouts to Gmail on Android:
To add Chat or Spaces to Android, first decide if you actually want Google Chat in Gmail. If you don’t, simply download the Google Chat app separately from the Play Store instead.
If you do want to integrate your Google Hangout with Gmail, download the Google Hangouts app from the Play Store. The app itself is now defunct, but when you open it, it will prompt you to move Google Chat to Gmail. Click the “Go to Chat in Gmail” and the Gmail app will update to now include “Chat” and “Spaces” buttons at the bottom.
You can then uninstall the Hangouts app from your Android device. The Google Hangouts app doesn’t appear to be necessary for continued use of the Chat functionality in Gmail.
Hope this helps someone else!