Are you using an iPhone 5 on T-Mobile? Are you in an area with re-farmed 1900MHz HSPA+ spectrum? Well rejoice! Some enterprising folks over at TmoNews have hacked Apple's carrier update for T-Mobile to boost data speeds on the 1900MHz (PCS) HSPA+ band. Better yet, this tweak applies to both T-Mobile's iPhone 5 and the AT&T / unlocked versions -- no jailbreak required. While the official carrier update enabled LTE for the iPhone 5 on T-Mobile, it also decreased data speeds on re-farmed PCS HSPA+ spectrum for many users. The hacked file makes a number of adjustments: it enables Release 9 for dual-carrier HSPA+ and sets the band preference to "auto" from AWS. Follow the source link below for more details and step-by-step instructions.