No , T-Mobile uses ussually full sim cards (Like a GSM network) and the Connect 4G Micro SIM only is for signal , No data on it , as most GSM networks you can save contacts on your SIM , so basicly No , The connect is a "CDMA 4G" phone
GSM Phones (Ussually FULL Sim Cards ) Work with Sometimes AT&T , Yes with Verizon , sometimes with sprint ,
CDMA Phones (Ussually only work with original carrier unless you do an illegal flash) are ussually Boost , Virgin , Metro , Sometimes Sprint
LG Motion uses a UICC Full Size Sim only for service , not contacts
LG Connect micro sim UICC only for 4G/Service
Phones like Sanyo Incognito , Samsung Messanger 2 Do not use Sims at all , so only the original carrier can activate it
(unless illegal flash)
Sorry its hard to explain , Point is , You would have to do something illegal to do that (lol)
Metro Phones Hard to Flash to a random carrier
Most AT&T Phones are compatible with T-Mobile
Most T-Mobile Phones work with AT&T
Most Sprint Phones work with Boost and Virgin Mobile (Same with other way around)
Most Verizon Phones work with either AT&T or Cricket
Most Cricket phones work with Virgin Mobile and US Cellular
Most Boring = I am done with the long list
-Mike from Verizon Wireless at peabody , MA
"Get the Galaxy Nexus from Verizon only for $159 , Only in select stores , Check online for more details , The power of jellybeans , Delicious at the touch!"