at&t
Verizon says their LTE phones will not be compatible with other carriers
Verizon does acknowledge that building devices that would work with Verizon and AT&T’s networks is possible but claims it all boils down to “business arrangements”. We’re guessing this is to make Verizon customers stay on or to make devices that are exclusive only to Verizon, but either way it might look a little manipulative, although we’d like to think of it as a good business strategy.