Apple announced a new iPhone Handoff feature in iOS 27 allowing users to share a single phone number across two iPhones and swap between them automatically. The feature requires carrier support and will launch exclusively on T-Mobile in the U.S. and Deutsche Telekom in Germany when iOS 27 releases on Monday, September 14. To use iPhone Handoff, users need two iPhones running iOS 27 or later connected to Wi-Fi and signed into the same Apple account with FaceTime, iMessage, and Messages in iCloud enabled.

Setup occurs during new iPhone configuration or via Settings, designating one device as the main iPhone and the other as secondary. The phone number activates on only one iPhone at a time, switching automatically upon unlock with a "Switched to this iPhone" confirmation. Carrier services like Call Forwarding and Caller ID remain manageable only on the main iPhone, and Apple Watch pairing does not transfer.

Payment cards and car keys in Wallet work across both devices, though transit passes, IDs, and corporate badges may be limited to one iPhone. Dual SIM is supported if both eSIMs are from supporting carriers, switching simultaneously. The feature persists until the carrier deactivates it.

T-Mobile has not yet announced pricing for the service.