When you accidentally send a message by mistake, you have a small window to unsend or edit it.
Successfully unsending a text will give you a confirmation in place of your rescinded message.
iOS 16 brought one of the most useful iPhone features last year, in my opinion — the ability to unsend and edit text messages. I've had my fair share of sending the occasional messages to the wrong person or having a typo, but this feature has helped me to quickly correct my mistakes.
If you make a grammatical mistake or even text the wrong person, you have 15 minutes to edit what your message says and two minutes to unsend it, essentially deleting the text. Want to know more about how the feature works? We'll explain it all below.
Now that iOS 17 is coming soon, within weeks after Apple's "Wonderlust" event, you might be interested in learning about the exciting new features coming with it. Also, here's some info on the new iPhone 15 coming this year.
If you use messaging tools like Slack, you've likely edited at least one — or 100 — of the messages you've sent. Whether you made a typo or your message contains incorrect data, the editing feature is a nice way to make your corrections quickly. With iOS 16, you'll also be able to edit your messages sent from your iPhone within 15 minutes of sending.
To edit a text message, you'll need to launch Messages and go into any thread that is using iMessage, which you probably know as blue text. This feature will not work with SMS text messages (green texts). Now, press and hold your finger down on the message you wish to edit. This will bring up the Tapback reactions and the quick action menu. Finally, tap Edit. 
Even if you edit a text message, the recipient will still be able to see any old messages.
The text message will then become editable. You can delete the entire message, fix any mistakes or add more text to it. Once you're finished, hit the blue checkmark button on the right side to save your edits. You can only edit a single message up to 5 times.
An actionable Edited button will appear underneath your edited text message. The person on the other end will also know that the message has been edited, and if they tap on Edited, all previous versions of your text message will appear above the edited text message, in slightly grayed-out chat bubbles. 
Accidental messages happen way too often. Maybe you tapped the send button when you meant to select an emoji. Or perhaps you messaged the wrong person entirely. In either case, you'll be able to recall those messages with iOS 16. Unlike with the edit message feature, you only have 2 minutes to unsend a text.
To unsend a text message, launch the Messages app, press and hold down on the message (blue text only) you want to unsend, and tap Undo Send.
The text message will disappear from your thread, on both your end and the recipient's. A message will appear on your thread, stating that your message has been unsent, but that the recipient may have already seen it.
You only have 2 minutes to unsend a text message.
Unfortunately, if the other person is running anything older than iOS 16, the message won't actually be unsent. The recipient will see a gray text status message that says, "[Name] unsent a message" if they've already viewed the text. This is similar to the Delete Message feature that apps like WhatsApp and Signal already have, which also shows a similar message after a text is recalled.
And if you edit a text message that's been sent to someone running iOS 15 or earlier, they'll receive a text message for every edit you make.
For more, these are the most annoying iPhone features and how to fix them.

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