I checked the PhoneUsage app and it told me Hootsuite was using all kinds of data today. I deleted it because I don't use it really at all so that must have been the cause. Powered off and then back on, the sync icon disappeared for a minute, but came back. So I guess it wasn't Hootsuite...although didn't hurt to delete if it is using that much data when I am really not "using" it. I guess I'll just go through and delete all of the accounts under "my account" and then readd them as needed.
Thanks!
Thanks!