# RPN King Calculator > Modern RPN calculator with gesture controls, periodic table, and OCR scanning. (iPhone/iPad app by Michael Stamm.) - Source: https://appshunter.io/ios/app/rpn-king-calculator/id1514004478 (this page in markdown: same URL + `.md`) - Developer: [Michael Stamm](https://appshunter.io/developer/1514004477) - Category: Utilities - Price: Free - Rating: 4.50/5 from 2 App Store ratings - Age rating: 4+ - Requires: iOS 12.3 · 70 MB - Languages: English - Released: 2020-05-20 - Data updated: 2026-06-10 - Monetization: free with in-app purchases - User reviews in markdown: https://appshunter.io/ios/app/rpn-king-calculator/id1514004478/reviews.md ## What is RPN King Calculator? A modern RPN calculator: Button and touch innovations take RPN to the next level in speed and convenience: "Just flick your way to the solution". Calculator completely free. Add-Ons (Table of Elements, OCR Number Scanner) as in-app purchase. innovations and add-Ons: 1. "Picking": swipe left/right on a button and any two more numbers on the stack can be calculated on - complete freedom to play with your numbers! 2. "Flick" up/down and buttons activate the 2nd and 3rd calculator functions 3. Table of Elements with many element properties to copy to the stack. Colored heat maps to show relative property distributions 4. Infinte Stack (scrolling) 5. OCR technology to scan in numbers to the calculator stack 6. unique scroll-wheel to quickly calculate TIPs for restaurant bills 7. dedicated memory buttons (also with flick technology: just swipe and tap, and the number is saved) The only app that combines the spirit of old calculators with new technology: You will not believe how intuitive and natural this feels: its like RPN was made for touchscreen: Being stuck to operating on two adjacent numbers is yesterday! The interface is fluid and intuitive for bringing your thoughts together, put numbers on the stack - contemplate them - manipulate. We designed for fluid gestures and made the experience thoroughly modern. Just enough scientific functions to be super useful - but not annoying. Dedicated memory buttons. Interactive Tutorial. World's first calculator that can scan in numbers with the camera. Beautiful periodic table with quick access to the reference data of elements - available for quick copy to the calculator. just rotate to landscape to bring it up. Big thanks to Mark Semadeni! Clever design and intuitive activation make this app a pleasure to use. ## Key features - Gesture-based RPN input - Infinite scrolling stack - Periodic Table add-on - OCR number scanning - Dedicated memory buttons - Interactive tutorial ## Frequently asked questions about RPN King Calculator ### What is RPN King Calculator? RPN King Calculator is a free utility app for iOS devices that provides a modern Reverse Polish Notation (RPN) calculator experience. It introduces innovative gesture controls for enhanced speed and convenience in calculations. ### How does RPN King Calculator differ from traditional calculators? It moves beyond traditional RPN by incorporating gesture-based input, allowing users to swipe on buttons and numbers for advanced operations. This aims to make RPN feel more intuitive and natural on a touchscreen interface. ### What are the add-ons available for RPN King Calculator? RPN King Calculator offers optional add-ons as in-app purchases, including a comprehensive Table of Elements with detailed properties and an OCR Number Scanner to input numbers directly from images. ### Is RPN King Calculator suitable for scientific use? Yes, it includes just enough scientific functions to be highly useful without being overwhelming. The app also features a periodic table add-on with quick access to element data, which can be copied to the calculator stack. ### Does RPN King Calculator have ads? The provided data does not specify if RPN King Calculator contains advertisements. However, it is listed as free with in-app purchases for add-ons. ### What devices is RPN King Calculator compatible with? RPN King Calculator is designed for Apple devices, including iPhone, iPad, and iPod. It is available for devices running iOS. ### How often is RPN King Calculator updated? The app was last updated on January 16, 2022, to version 1.1.4. This indicates a moderate update frequency, with the developer actively maintaining the application. ### What is the user sentiment for RPN King Calculator? RPN King Calculator has a high rating of 4.5 stars from 2 ratings, suggesting positive user reception for its innovative features and intuitive design. ## Version history (last 1 release) ### 1.1.4 — 2022-01-16 button deadspeace decreased by popular demand (more reliable typing) iPhone 12 and 13 sizes now working properly ## Apps similar to RPN King Calculator | App | Rating | Price | Category | | --- | --- | --- | --- | | [武威慧停车](https://appshunter.io/ios/app/id1448009640) | — | Free | Utilities | | [佐敦](https://appshunter.io/ios/app/id1448255140) | — | Free | Utilities | | [MISD Tip](https://appshunter.io/ios/app/misd-tip/id1440174120) | — | Free | Utilities | | [Omni Relprev](https://appshunter.io/ios/app/omni-relprev/id1434690340) | — | Free | Utilities | | [Pf Fidelity](https://appshunter.io/ios/app/pf-fidelity/id1434839440) | — | Free | Utilities | | [ASOS-IndustriALL İşçi Hakları](https://appshunter.io/ios/app/asos-industriall-isci-haklar/id1440516280) | — | Free | Utilities | --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*