What happens on Google Photos apparently stays on Google Photos, even if you've deleted the app from your device. An interesting, and potentially scary, aspect of Google's Photos app has been discovered that anybody who has ever used the application should be aware of.
David A. Arnott of the Nashville Business Journal recently learned that photos he was taking on his Android phone were being backed up on Google Photos even though he had long since deleted the app from his phone. Obviously, he was more than a little disturbed that pictures he thought were only on his phone were out in the cloud.
It turns out that when you turn the "back up & sync" setting on for Photos in your Android phone, you're not actually accessing the setting in the app, but in the phone itself. If you delete the app, the setting remains, so all your photos will continue to be backed up to Google Photos even though you no longer use it. Since most people probably don't make a deep dive on their phone settings on a regular basis, it's pretty much a set it and forget it thing, it's very possible that many users have photos in the cloud they don't know about.
If you have an Android phone and have ever used Google Photos take a moment and check your phone settings and be sure your photo sync is turned off, unless you want it on of course. It's difficult to function these days without putting some data in the cloud, but at the very least users need to be aware of what is out there.