Can anyone help? I have rooted and am using Viper ROM. I have a 4G sim but cannot get 4G. I have checked with my network and they state there is no problems with their service. They have exchanged my sim card and I still have no 4G. I have downloaded an app from my network provider which can check your phone for 4G and it states my phone is not 4G enabled. Do we know what could be causing this? I am on the tesco mobile which uses o2's network in the UK. I downloaded their app when I took out their 4G service. This is the app that told me my phone was not 4G enabled. I have an unlocked M7 UL 64GB HTC One.