I recently got a new Android phone, and my mom started using my old Android phone. Neither of us knowingly set up photo backups or cloud storage, but photos, screenshots, and WhatsApp images taken on either phone are appearing in the other phone's gallery. We're probably sharing an account somewhere, but I'm not very comfortable with technology. What's the simplest way to separate the two phones and stop the photos from syncing?
2 Answers
The phones are probably signed into the same Google account, which can make Google Photos sync pictures between them. Check the Google account on each phone and make sure you use separate accounts. On each device, open Google Photos, tap the profile picture, go to Photos settings, then Backup, and turn off backup if you don’t want cloud syncing. Also check the phone’s Accounts section and remove the other person’s Google account. Back up or transfer anything important first, since removing an account can affect synced data.
If both phones are Samsung, check whether they’re also using the same Samsung account. Sign out of the shared account and set up separate Samsung and Google accounts. Since your mom is using your old phone, a factory reset is the cleanest option after saving anything you need from it. During setup, don’t restore it with your Google or Samsung account; use her own accounts instead.

Thanks! I’ll check the Google accounts and turn off the photo backup before removing anything.