When you turn on
HTC One SV for the first time, it will be automatically set up to use your mobile operator's data connection (if the micro SIM card is inserted).
HTC One SV is available in either a 3G-only or 3G-and-LTE version, depending on what's supported by the phone you purchased and your mobile operator. You need an LTE plan to use your operator's 4G LTE network for voice calls and data services. Check with your operator for details.