T-Mobile has few 3G mobile phones in its portfolio, and Sony Ericsson has just joined in with the first phone from the company on this network, but also the first 3G phone.

T-Mobile's 3G network supports the UMTS 1700Mhz band, and the network is planning on rolling out HSDPA as well.

The Sony Ericsson TM506 is a mid-range device with a 2 megapixel camera, a M2 memory card slot, 3G (obviously), and built-in A-GPS with TeleNav navigation software.

The price hasn't been announced yet, but the release date for the TM506 should be in early September.

Sony Ericsson TM506 official specifications:

TM506 Phone At-A-Glance

• Weight: 3.4 ounces
• Size: 3.7 x 1.9 x 0.69"
• Talk Time: Up to 9.5 hours GSM; up to 3.5 hours UMTS
• Standby Time: Up to 250 hours GSM, up to 250 hours UMTS
• 2.0 Megapixel Camera
• Media Center
• aGPS Built-in
• TeleNav®  Navigator
• RSS Feeds
• MyFaves-enabled
• Audio Postcard
• Quicksend
• Mobile Backup (T-Mobile Address Book)
• Bluetooth® 2.0 / A2DP / Stereo streaming
• Tri-Band GSM (850/1800/1900)
• Dual-Band UMTS (1700/2100 & 2100)
• GSM/GRPS/EDGE/UMTS/HSDPA

[via Electronista]