Apple Pay Cash premieres in the US

Apple Pay Cash has arrived to US customers, enabling person to person cash payments through Apple Pay and iMessage.

The feature was first supported in the iOS 11.2 beta 2 but was not ready by the time the final iOS 11.2 rolled out a few days ago.

Apple Pay Cash supports iPhone SE, iPhone 6 and newer, iPad Pro, iPad 5th Generation, iPad Air 2, iPad mini 3 (or later) while Apple Watch users need watchOS 4.2 to use Apple Pay Cash.

You need to restart your devices before they can start to send and receive money.

Currently a US exclusive, there's no timeframe for the eventual international rollout.

Source