I am having some serious issues with push on 5.1. Doesn't matter if I am on wifi or cell network push is not working properly. I have tried resetting network settings and restarting the phone and force closing mail and deleting my account and re entering it and nOthing seems to work. Occasionally it will push but the majority of the time it does not. Doesn't seem to be as bad on my new iPad as it is on the iPhone. I have tried a 4 and a 4s and both are hit or miss. My 4s came with 5.1 and I have no way to dOwngrade it but this is very frusterating. I can't get push with iCloud or gmail or hotmail (both as exchange) and the settings are the same as on my iPad which works much better. Any suggestions?