If smartphone user interface designers are reading this blog I have a feature request: I need a 3G/4G only switch in the settings to disable GSM while leaving the device the option to roam between UMTS and LTE. Let me explain:
Last year I decided to set my smartphone I use for voice and small screen web browsing to '3G only' mode to prevent fallback to GSM, as HD-Voice (WB-AMR) continues to be only deployed in 3G, and dropping to GSM during a call results in a noticeably worse speech quality. Also, I like receiving my emails during lengthy conference calls and get some background information over the web sometimes which is also blocked after a fallback to 2G. Also, air interface security is better on 3G. So far, so good, this works well.
For data connectivity for my notebook on the daily commute and on longer train trips I use Wi-Fi tethering to another device that is LTE capable. Unfortunately, LTE is not as widespread as 3G yet so I have the network type selection set to 2G/3G/4G. This way, I get LTE when it's available in stationary places and 3G on the train as LTE coverage is still somewhat patchy. Hence the device is then stuck on UMTS for the rest of the trip because there is currently no way to get from UMTS to LTE while in Cell-DCH state. But it's still mutli-megabits per second so no real complaints here for the moment. Not so good, however, is that the connection sometimes even drops to GSM and then it takes quite a while to get back to UMTS as the device is busy transmitting data and has only little time to search for a reappearing UMTS network. But these days, GPRS or EDGE are almost unusable for the amount of data that I consume on the notebook so I wonder if that fallback still makes sense?
Therefore I'd rather like the Wi-Fi hotspot device not to fall back to GSM at all and just 'ride-out' the temporary lack of UMTS coverage as I have the impression that the device finds the UMTS network again much faster. Obviously I can set the device to UMTS only mode just like my smartphone but then I disable LTE as well which I really like in stationary places due to the much faster uplink compared to UMTS. In other words, I'd really like to see a 'UMTS/LTE-only' mode setting.