About this app
RPN Calculator 48 is a polished RPN replacement for Apple's calculator app: - Same scientific functionality as Apple's calculator app* - Use swipe gestures to undo and redo operations! - Starts quickly - Large buttons - Easy-to-read display - 100 entry stack - 6 memory buttons (A-F) - 50+ levels of undo/redo - Saves state on exit The ergonomics (screen and keyboard layout) of RPN Calculator 48 were inspired by HP's outstanding 48-series calculator. RPN Calculator 48 is made by the developer of tChess (the critically acclaimed iPhone chess game) and Learn Chess (the Apple Staff Favorite e-book). * This app is not an HP 48 emulator.
Latest release
What’s New
- Added support for hardware keyboards - Added an option for haptic feedback in the main menu
Audience growth
Ratings growth
Baseline captured. Growth appears after the crawler observes a changed rating count.
Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.
Price tracking
Price intelligence
First snapshot captured. The trend line starts after the next crawler price observation.
- First observed Aug 24, 2026 · 7:28 AM $3.99
Screenshots
