Google+ Background Data Usage My 1GB data pack (3G) was running out a bit faster than normal, so I started investigating using the Data Usage tool (Android 4.1.2 Nexus S).
That's when I found out the Google+ app had used 300 MB in 3 days, and all of it was background data.
Here's the graph:


Graph (click to enlarge)

I don't remember using the app much at all, yet it almost burned through my data pack. I've set the Instant Upload settings to only upload when connected to Wi-fi, and roaming uploads are disabled too. I disabled background as soon as I figured it out, but I still don't know how and why it used up so much data. Any pointers?
Google Photos auto-backup may sync automatically the local photos to account.turn of this feature if you don't need it.