I understand that one of my three gmail accounts was used to set up my phone, but I am not sure which. I do want to be able to toggle between all three with email, contacts, calendar etc. I do NOT understand the difference between the gmail and email apps ... it appears I have all 3 accounts in email and 2 of them on gmail app. I use email and don't even have the gmail app on a screen. Everything has been fine until today. The accounts are there and permit me to send email, but the older messages have vanished and it is not receiving new messages. No error message. It is just empty. Everything is fine on computer. The only things I did today that are different. I went into G+ app and logged out from one account and back in as other. Then reverse. That's exactly when email disappeared. I tried removing and reinstalling accounts starting with one I know isn't the "mother" account and the phone said I don't have permission. I also opened the gmail app and nothing happened. Not able to synch. Not able to remove or add. Sigh. This is very frustrating. I really need email access from my phone. Using the browser is exhausting. Help?