PCalc

PCalc combines scientific arithmetic, number bases, unit conversions and programmable functions on Apple devices. The linked 2017 manual explains RPN as a stack: Enter pushes a number, operators combine stack values, and Drop, Roll and Swap manage them. It also documents a 128-level stack with an optional four-register mode and a separate operator-precedence setting for ordinary entry. The tape records working and can be copied; the guide distinguishes Mac saving from iOS emailing. Current Mac documentation confirms editable functions/conversions, synchronization and Handoff, with a Mac App Store purchase. Check edition requirements and entitlements when moving among Apple platforms.