So I've done a google search and have found other users having this problem but no solutions or even possible solutions. Intermittently, when leaving a wifi connection (my home or office) I completely lose all data connection. The "signal" bars still show 4 full bars, but there is no 3g or 4g connection. I have tried, disabling the wifi, I have tried disabling and re-enabling the data network, I have tried opening other apps that use data and get "waiting for connection" or "no connection found". The only thing I have found that fixes it is a complete reboot. What is even more annoying, it doesn't always happen, or only happen with certain networks. It just seems to happen when I need it the most, like when I am about to start a run, or get directions!