alphadogg writes "Sprint, which has been building up its LTE smartphone lineup this year, Monday finally turned on a 4G LTE network in 15 cities to support those devices. Sprint, which is entering the LTE network race well behind AT&T and Verizon, has initially launched 4G LTE in cities across Georgia, Texas, Missouri and Kansas. Sprint says it will add markets throughout the rest of 2012 and expects to have largely completed its 4G LTE build-out by the end of 2013 (along with enhanced 3G coverage) to address the wireless voice and data needs of 250 million people across the United States. Sprint has some major catching up to do on the 4G LTE network rollout front, though the fact that LTE adoption by customers has been slow at least gives the carrier a bit of breathing room. LTE network demand is expected to surge later this year, assuming Apple rolls out an iPhone 5 with LTE support."