This is a calculator app for Apple Watch.
To make it easier to input on the screen of AppleWatch, it has the following functions.
Delete an entered numbers: You can delete entered character by the red button on the upper left of the screen.
Change a number with digital crown: Turning the Digital Crown, you can correct the number.
voice input & "scribble" input (beta version): You can also calculate by entering expressions with voice or handwriting (Scribble).
(If your language does not support "Scribble", press the "Voice Input/Scribble/" button on force touch menu, and select English from "Choose Language".)
Moreover, it is possible to calculate "tax" and "w/o tax".
At first, tax value is 8%. Press the screen strongly, select "Settings" from the menu, you can change the value.