On the iPhone, you can undo an action by simply shaking the smartphone. Here's how it works
How many times have you typed text in Word or another Windows or Mac app and made a mistake? How many times have you accidentally deleted a file? How many times have you edited an image and the mouse "escaped" and you made a disaster? In all these cases you didn't worry too much, because you had the "Undo" command available on your computer and you could use it comfortably from the shortcut CTRL+Z on Windows or Command-Z on Mac.
Well, you have this feature on your iPhone, iPad and iPod Touch too, even if you might not know it. It's called "Shake to Undo" and it's been available for quite a while, as Apple introduced it back in iOS 6. As the name implies, if this feature is enabled just shake your iOS device and it will undo the last action you took. To be precise a pop up message appears asking us if we want to undo it, or keep it. In iOS 13 also came an additional feature to do the same thing, in a more sophisticated way. "Shake to undo" is a little-known feature that divides users: there are those who use it all the time and there are those who can't stand it.
How to enable/disable Shake to Undo
Enabling or disabling the "Shake to Undo" feature is super easy: just go to Settings > Accessibility > Tap and we'll find the toggle to do it. When it is active we just have to shake the iPhone, iPad or iPod Touch and a message will appear with two buttons: "Ignore" and "Cancel". And it is precisely this message that has convinced many users to disable the feature, because if you press "Undo" actually does not undo the error made but "undo the undo" and the error remains and can no longer be corrected. Many users, then, complain that this feature is activated too often on its own, since you just have to move the device a little too quickly.
The alternative on iOS 13
The idea behind "Shake to Undo" is good, even great: having the ability to undo a command makes us feel much more comfortable. That's why Apple introduced in iOS 13 new gestures to do the same thing even without activating "Shake to undo": doing a three-finger swipe to the left we undo the command, while with a three-finger swipe to the right we restore it. Doing a double tap with three fingers, instead, a small menu appears with five buttons: undo, cut, copy, paste, restore. Those who don't like "Swipe to undo" because they find it inconvenient, therefore, can opt for this second option and have the same functionality.