Calc boy is a simple calculator styled as a physical device, based loosely on an old Braun calculator.
It only performs simple mathematical functions, including addition, subtraction, multiplication and division. It does also allow for decimal points, and displays not only the current input or result, but a running sum until the entire expression is evaluated.
A working demonstration is hosted at Netlify, and you can visit it and try it out using the visit website button at the top of this page. The code is hosted at Github and you can visit this using the github button, also at the top of this page.