The inclusion of push notification support means third party developers no longer have to poll Gmail for new messages, which helps eliminate time and extra network costs. As Google puts it, “Just subscribe to a Gmail mailbox and whenever a change occurs, the Gmail API will instantly notify your server.”
Although you can still use IMAP, the official Gmail API will support all the features that come with Gmail, such as drafts, replies and native search, to name a few.
For more info on what you can do with the new update, read the developer’s guide here.
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