This phone is the best performance per dollar smart phone for the people who can get TMobile HSPA+ connection. The HSPA+ data download and upload speed are 3Mbps - 8Mbps and 500kbps - 3Mbps. If one is not on the HSPA+ network, the phone will switch to EDGE network, and the data download and upload speed will be reduced to 40kbps - 100 kbps and 40kbps - 120kbps. GroveIP + Google Voice combo do not work really good on Tmobile EDGE network because the data speed is way too slow. The GroveIP voice will either be lagging or breaking up and it''s an unacceptable calling experience. The same result applies to Skype, however if one switch to a good Wifi network and then this wont be a problem. But we all know that using Wifi means you have to stick in that room, so don''t even dream about driving and use GroveIP to call someone on a wifi network at the same time.Tmobile post paid call centers people are in US but the pre-paid ones are not. It may not be a fun experience to deal with the pre-paid customer agents. It took me about 4 hours to switch from a post-paid Tmobile account to a pre-paid $30 100 min, unlimited text and data plan. It is very tricky on how to move my post paid phone number to a pre-paid service and also select this $30 100 min unlimited plan.The default Tmobile Wifi calling app does use your own plan minutes when you make a call on a Wifi network. I think this is lame and it is wrong.The battery lasts about 2 days of usages if one is on EDGE network. The battery lasts less than 1/2 day if one uses HSPA+ and playing with video and music.I got this phone for about 2 weeks.The phone supports Tethering and Portable Hotspot but by default, Tmobile will block the service even if you have unlimited data plan. Additional cost is required to use this service.A screen protector is not needed. I just keep the original MFG plastic screen cover on and let a 9 years old kid to play Fruit Ninja for about 1 hour, as result, it works fine, no damage on the phone screen.The front phone cam produces really crappy image quality. But it is still useable to let others see you.As of Jan 19, 2012, I think this phone will not get Ice Cream Sandwich upgrade.Overall, this phone is not as good as iPhone 3GS, no where near iPhone4 and iPhone4S. But for $189, this is still the best value phone when using TMobile $30 100 minutes, unlimited text and unlimited data monthly plan.********************************************************************************************************Updated April 21, 2012Dial *#*#197328640#*#* and option 1->8->7->2->2 to use 3G/4G network only.Dial *#7465625# to see if the phone is locked or not.