How to unsend an email in Gmail on a computer or mobile device, and change how long you're able to unsend messages

You can unsend an email in Gmail on a computer or mobile device with Google's Undo feature. Messages can be recalled up to 30 ...

How to delete all your emails on Gmail, or mass-delete a specific amount of emails at once

To mass-delete all your emails on Gmail, click the "Select" box, then "Select all conversations." Or you can choose specific ...