We'd heard rumors that T-Mobile would take advantage of its MetroPCS deal to offer bring-your-own-device service to more customers, and it isn't letting us down with the launch of MetroPCS' Bring Your Own Phone. Much like T-Mobile itself, MetroPCS can now offer its plans to customers with unlocked GSM phones. Don't be too quick to hop aboard, however. Only those in Boston, Dallas, Hartford and Las Vegas can switch service right away, and the carrier's official support is limited to Android, iPhone and Windows Phone devices. Should everything line up, though, Bring Your Own Phone is available today.