[TUTORIAL] Unlock Your SIM Mode [Buttery Easy Style]
Unlocking your sim mode is very easy in HTC Sprint One
Steps To Follow:
1- Unlock Your Bootloader (Google around)
2- Open your dialpad and dial " *#*#4636#*#*
3- Tap on Phone Information
4- You will see a black screen with lots of things. Scroll down and find " Set Preferred network type "
5- You will possibly see CDMA+evdo or something like this.
6- Click on it and scroll down or up to find GSM only.
7- Turn off the radio and turn the radio on after 30 secs.
8- Restart your device and you are DONE!
Let me know if it helped