How do you know if you have toggled off 4G on the Thunderbolt? Will it no longer show "4G LTE" next to the signal bars? If that's accurate and that indicates coming off the 4G network then I think I have found a built in widget that lets you do it. I don't necessarily consider myself tech-savvy because I think I more or less stumbled on it while experimenting with the features of the phone. Let me know if I'm not on the right track here or if I'm wasting anyone's time. I will post how to do it if anyone thinks that if the "4G" indicator is off that your are, in fact off the 4G network. Thanks.