Mobile carriers have been the bane of my existence for as long as I've had a phone. First, they take away unlimited data, and then when you try and switch carriers, they hold your phone hostage for a up to a week before unlocking it from their network.
There are services out there that can unlock your phone right away for a fee, but why not do the same thing right from your own home? Thanks to the people over at Sieempi, there is a way to SIM-Unlock any HTC One that is already S-Off!
What You'll Need
You'll need a couple of different things, depending on which HTC One you have: