Apple tied the iPhone duo release date to iPhone Handoff last month, when it unveiled the Duo and the feature that keeps one phone number active on two iPhones at the same time. The setup changes how people can split calls and account use between a main phone and a secondary phone.
Apple and iPhone Handoff
Apple says the user picks one phone as the main phone and sets up Handoff on the other as the secondary phone. When one of the iPhones is unlocked, the number becomes active on that phone. That phone receives calls and is used for Find My.
T-Mobile charges $5
T-Mobile is the first US carrier to support iPhone Handoff. It adds $5 to the monthly phone bill for the feature. The secondary iPhone should not have any other service attached to it, which narrows the setup to people who want a second device without a separate line.
Verizon and AT&T support
Verizon is planning to support Handoff by the end of the year. AT&T does not support Handoff at launch. T-Mobile also says the secondary iPhone cannot be used with a T-Mobile business account at launch, so business users do not get the same path as personal accounts.
Apple is pitching a cleaner way to move between two iPhones, but the rollout starts with carrier limits and an extra monthly charge. People weighing the Duo against phones such as iPhone Air and iPhone Mini now have a narrower question: whether one number on two phones is worth the fee and the restrictions.
