The ability to undo sending an email was already available on the Inbox app for iOS and Android. But version 8.7 and up of Gmail for Android now also includes the feature, according to Android Police. A Google support page also notes you can recall a message after hitting send on the Android app., as well as on its
Here's how to take advantage of the feature: After sending an email, you'll see a message pop up at the bottom of the screen giving you the option to cancel the message before it's sent. Hitting "cancel" brings you back to the draft of your email. If you don't hit cancel and the email is sent, you'll see a prompt giving you the option to "undo" the send. Hitting that also brings you back to the draft of the email.
If you're sending an email to another Gmail user, Google will pull the email back, according to Android Police. Messages to other email services reportedly experience a slight delay, which means you can stop the message from sending with the undo button if you change your mind.
Google didn't respond to a request for comment or confirmation on when the Gmail Android app feature rolled out.