I'm on stock, data connection seems fine. Normally, I open the mail app to manually sync it, and then I back out of it and browse the Internet while it finds all the new mail. I happened to go back to it and see that it was still "loading mail". Now it does it every time I open the app, and I can't seem to get it to stop. I hoped restarting/ powering on and off the phone would remedy it, but I turn off my phone at the end of the day every day, and when I turned it back on today, it was still doing it.