[MrVeda]

I may have missed this in other threads but any early up-graders to OS 7.1 on T-Mobile 9810 tried the WiFi Calling yet? I know it's not UMA but how good is it? Call quality? Does it drain the battery?

[ealvnv]

works on the 9900, is very good, call quality also deppends on wifi quality, nope it doesn't, in fact it saves some battery

[invisible_man]

Yes, it works on the 9810 as seen in the attached image. Call quality is far better than the UMA I had on my 9800 using the same router setup. Battery drain of 7.1 for me seems to be about 7%/hour, which is far from good, but I'm usually around a charger so not an issue for me. Others have reported far superior battery life, but it seems to vary widely.