Is it possible to turn 3G off (and have GPRS)? The only option on my 4S under Settings > Network is to turn the cellular data off. On my previous 3Gs it was possible to turn off 3G and force it to revert to GPRS. (Why do I want to do this? The 3G data service on both O2 and Orange where I work is pi$$ poor because the single transmitter is serving thousands of people. I want to try turning off the 3G service and reverting to GPRS to see if I can trickle data through).