Your Apple Watch can't send emails, but it can make dealing with them a whole lot easier.
Everyone has a different system for sorting emails, whether it's Inbox Zero, and trying to delete everything of unimportance, or flagging and marking emails you need to respond to as unread. Your Apple Watch can't reply to incoming emails from the Mail app, but it can make sure that they're easier to deal with when you return to your iPhone, iPad, or Mac.
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