For a week or two, my iPhone 5 has been registering full bars with 4G coverage, but I have no data connection. I can't send an iMessage, load my twitter feed, go to a website, nothing. Text messages and phone calls work fine, as does Wi-Fi, it is just 4G data that doesn't work. I scheduled an appointment with the Genius bar this afternoon, but my worry with that is it can be hard to prove it because it doesn't happen all the time, probably only 30% of the time. I've also noticed when this happens that my battery will drain SUPER fast. This morning I went through 10% battery in about a half hour, just being on twitter for maybe 10-15 of those minutes. A few days ago I went through 30%+ in 2 hours with my phone locked and nothing open with the exception of Tweetbot and using it minimally. Is this a known issue? My roommate is also on ATT with a 4S so I know it's not an issue with the network in my area.