Just opened Drive after upgrading to a family plan and saw that I got access to “Photo Backup”. I contacted support about the iOS beta when it was announced and was told that it’s not yet available for iOS. I am using the TestFlight version but not sure when this came through.
EDIT: I added a link to a folder on Drive which contains some screenshots from the iOS app.
I’ll add some screenshots to the original post shortly.
As for how it’s going? It’s best summarised as “basic”.
It works fine, it acts as a simple backup solution. I would like to see it developed a little more though. Having said that, I’m not sure if the Android app differs in any way.
EDIT: Just noticed that it seems to check through all of your photos again when trying to backup after the app has been closed. It doesn’t take very long but it’s still there.