Unsubscribe from mailing lists
If iOS recognizes the email as a newsletter from a mailing list, you will get the following notification above the sender’s info: “This message is from a mailing list.”
This trick enables you to only receive newsletters that are really interesting to you. The daily routine of deleting unread emails that you are not interested in will eventually take less time, if you follow this trick to unsubscribe from all unwanted newsletters.
Sometimes it happens that iOS does not recognize a newsletter as a newsletter. Then you can still do it the manual way.