CP HexCalc - Hex Calculator for the iPhone/iPod Touch
RPN Hex Calculator
GitHub - alpiepho/rpn-calc-vscode-extension: Simple RPN (reverse polish notation) Hex calculator as a Visual Studio Code extension. RECENTLY published on MS Marketplace!
IntCalc for Mac OSX by InerTron Software
calc.50x.ca Hex Decimal Binary Converter | Michael Kafarowski