Correct, the SIM800 line are 2G only which I believe is only provided in the US by T-Mobile as you mentioned. In the UK things are a little different, where the

Correct, the SIM800 line are 2G only which I believe is only provided in the US by T-Mobile as you mentioned. In the UK things are a little different, where the vast majority of the core mobile network providers still supply 2G networks, but I believe some of them have published plans to decommission them within the next couple of years. In terms of 3G, 4G and LTE modems, they’re a little harder to come by quite so readily, and are a damn sight more expensive too! You can pick up an 800L for £1-1.50, for 3G it’s close to £20-30 from what I remember.