Calculators are amazing. They have the ability to do seemingly impossible math in a matter of seconds but anyone who has added a bunch of things together only to mistype a number knows how annoying they can be too.
However, it turns out the designers of the iPhone calculator know that pain and added into it a secret backspace function!
If you swipe the numbers left or right, it will remove the most recent digit added. Twitter is rightfully blown away by the revelation: