Until today, the iPhone’s calculator mimicked the buttons of its forebears: If you keyed in 48.375, for instance, instead of 43.875, tapping “C” within your app would zero out your entry so ...

The 4×4 keypad connects to the Arduino’s digital pins, with rows attached to pins D9, D8, D7, and D6, and columns to pins D5, D4, D3, and D2. A push button is wired to ground and connected to pin D10 ...

Most of the mods using Game Boy and other retro gaming consoles feature some sort of new technology modded into an old console, but modder Alexis Sepúlveda decided to put a calculator inside a ...