Last year, when Apple released iOS 18, it introduced several significant changes to the iPhone’s Calculator app. Basically, it gave it a bunch of new abilities.
The headline new feature was Math Notes, which allows you to type or write math equations, and then the app will solve them for you. It also introduced a Converter function for quickly converting things like currencies, lengths, volumes and temperatures.
That said, one smaller thing that Apple did with iOS 18 was tweak the button layout of the basic Calculator app, which irked some people.
And now, with iOS 26, it seems to be looking to right that ship.
A button returns

Specifically, iOS 18 removed the traditional AC/C (stands for “All Clear” and “Clear”) button from the calculator and replaced it with a back button. If long-pressed, the new back button did the same function as the previous AC/C button, but it can also delete one digit at a time, like the Delete or Backspace button on your keyboard.

