The latest software update for Apple Watch is now available, just a few days after Apple released iOS 11.2 earlier than expected. The biggest link between the iDevice and Watch software updates is Apple Pay Cash, which is now available for Apple's wearable in watchOS 4.2
Apple Pay Cash lets US-based users send and receive money through iMessage, with funds drawn from a linked credit or debit card. Those who receive money get it in the form of an Apple Pay Cash Card, which they can then use to pay for things through the Apple Wallet app or transfer that money to a bank account. On the Apple Watch, users can tap the new Apple Pay Cash button at the bottom of an iMessage conversation to initiate a payment to that contact.