# RPN Calculator Pro > HP-like RPN calculator optimized for small screens with large buttons and display. (iPhone/iPad app by Dr. Oliver Fox.) - Source: https://appshunter.io/ios/app/rpn-calculator-pro/id453748959 (this page in markdown: same URL + `.md`) - Developer: [Dr. Oliver Fox](https://appshunter.io/developer/334264533) - Category: Utilities, Productivity - Price: $1.99 - Rating: 5.00/5 from 2 App Store ratings · 3 written reviews indexed - Age rating: 4+ - Requires: iOS 7.0 · 2 MB - Languages: English - Released: 2011-08-05 - Data updated: 2026-06-10 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/rpn-calculator-pro/id453748959/reviews.md ## What is RPN Calculator Pro? The HP-like Calculator is especially designed for the small screen! The biggest display and the biggest buttons of all RPN calculators for the iPhone. With a simple touch in the LCD Display all hidden function slide in when they are needed. Fast, simple, easy and fun to use. - The ultimate every day HP-like Calculator for iPhone, iPod Touch and iPad. ******************************************************* ●● RPN Calculator Pro - The HP-like Calculator that is specially designed for the small screen! ●● - The ultimate fast, simple and easy to use HP-like Calculator for your iPhone. - Specially designed for the small screen. - The biggest display and the biggest buttons of all RPN calculators for the iPhone. - With a simple touch in the LCD Display all hidden functions slide in when they are needed. - Fast, simple, easy and fun to use. - All required features packed in the most useful design. - The ultimate fun and fast HP Calc for iPhone, iPod Touch and iPad. ******************************************************** You’re looking for a quality HP Calculator replacement for your iPhone? Maybe one that’s been especially designed for the use with the small screen? Well, look no more because you’ve found it. - RPN Calculator Pro has the biggest Display and the biggest buttons of all RPN calculators for the iPhone! - With a simple touch in the LCD Display all hidden function slide in when they are needed! - RPN Calculator Pro is 100% accurate and reliable for your most precise financial and scientific calculations! - RPN Calculator Pro is always at your fingertips on your iPhone, iPod Touch or iPad and it only costs a fraction of what you have to pay for a real HP model! The app arrives fully loaded with all the features you would expect in a dependable HP-like Calculator: ● Extremely fast start up, almost instantaneous ● Biggest display possible ● Biggest buttons possible ● All basic and scientific calculator functions ● Customizable settings ● Undo function ● Numerous Stack functions ● Sound Feedback (On/Off) ● Fun to use ●● RPN Calculator Pro is the HP-like Calculator you want on your iPhone. Not only is it reliable and precise, it’s also very, very fast and fun to use. RPN Calculator Pro is always at your fingertips on your iPhone, iPod Touch or iPad. It only costs a fraction of what you have to pay for a real HP model. And it is specially designed for the use with the small screen hence it is more fun to use than most of the other HP emulators out there... ●● ●● The ultimate fun and fast every day HP-like Calculator for the rest of us. ●● With the next updates there will be more and more functions according to user demands Grab it now and enjoy all the FREE updates! ## Key features - Largest display and buttons for RPN calculators - Hidden functions accessible with a touch - Fast, simple, and easy to use - 100% accurate and reliable - Basic and scientific calculator functions - Undo and numerous stack functions ## Recent user reviews (3 of 3) All indexed reviews: https://appshunter.io/ios/app/rpn-calculator-pro/id453748959/reviews.md ### 5/5 — Awesome *2012-04-23, version 1.0* I've always preferred RPN for doing calculations and this free app is simply awesome for my basic needs. If I had the time to reacquaint myself with an HP 41 style app, that would be awesome but this app works just fine on a daily basis. ### 5/5 — Simple, powerful and fun to use *2011-10-08, version 1.0* Definitely smart design. Biggest display and the biggest buttons of all HP like - calculators out there… All hidden functions slide in with a simple click in the display - Simple, powerful and fun to use: 4-5 Stars! ### 5/5 — Loads fast *2011-09-23, version 1.0* Shows promise. Support dev and take it for a spin. ## Frequently asked questions about RPN Calculator Pro ### What is RPN Calculator Pro? RPN Calculator Pro is an HP-like calculator application designed specifically for small screens. It features the largest display and buttons among RPN calculators for iPhone, offering fast, simple, and accurate calculations. ### Is RPN Calculator Pro accurate? Yes, RPN Calculator Pro is stated to be 100% accurate and reliable for precise financial and scientific calculations. ### What devices does RPN Calculator Pro support? RPN Calculator Pro is available for iPhone, iPod Touch, and iPad, and is also supported on Apple Watch. ### How much does RPN Calculator Pro cost? RPN Calculator Pro is a paid application and costs $1.99. This is a fraction of the cost of a physical HP model. ### Does RPN Calculator Pro have ads? The provided data does not indicate the presence of advertisements in RPN Calculator Pro. ### When was RPN Calculator Pro last updated? RPN Calculator Pro was last updated on January 12, 2016, with version 7.1. ### What are the key features of RPN Calculator Pro? Key features include the biggest display and buttons, hidden functions accessible by touch, fast startup, basic and scientific functions, an undo function, and numerous stack functions. ### What is the age rating for RPN Calculator Pro? RPN Calculator Pro has an age rating of 4+, making it suitable for a wide range of users. ## Version history (last 1 release) ### 7.1 — 2016-01-12 This app has been updated by Apple to display the Apple Watch app icon. fixed display bug... ## Apps similar to RPN Calculator Pro | App | Rating | Price | Category | | --- | --- | --- | --- | | [RCL-57](https://appshunter.io/ios/app/rcl-57/id1621959742) | — | Free | Utilities | | [Emu50g](https://appshunter.io/ios/app/emu50g/id553279622) | 4.1 (42) | $8.99 | Utilities | | [Halcyon Calc Lite](https://appshunter.io/ios/app/halcyon-calc-lite/id408004888) | 4.7 (15) | Free | Utilities | | [SpicyRPN](https://appshunter.io/ios/app/spicyrpn/id1474140612) | — | $9.99 | Utilities | | [RPN Anywhere](https://appshunter.io/ios/app/rpn-anywhere/id1250545319) | 4.5 (28) | $0.99 | Utilities | | [GO-25 SciRPN](https://appshunter.io/ios/app/go-25-scirpn/id408249517) | 4.7 (23) | $4.99 | Utilities | ## More apps by Dr. Oliver Fox - [Sport Log Ultimate Free - Plan, log, analyse and export training and fitness](https://appshunter.io/ios/app/sport-log-ultimate-free-plan-log-analyse-and-export-training-and-fitness/id797812544) - [Gym Log Ultimate Free - Plan and log workouts with the best fitness tracker](https://appshunter.io/ios/app/gym-log-ultimate-free-plan-and-log-workouts-with-the-best-fitness-tracker/id797817630) - [Car Log Ultimate Free - Car Maintenance and Gas Log, Auto Care, Service Reminders](https://appshunter.io/ios/app/car-log-ultimate-free-car-maintenance-and-gas-log-auto-care-service-reminders/id797830569) - [Money Log Ultimate Free - Save your pocket money, track expenses and income](https://appshunter.io/ios/app/money-log-ultimate-free-save-your-pocket-money-track-expenses-and-income/id798650160) - [Work Log Ultimate Free - Plan, Log, Analyze - time tracking made easy](https://appshunter.io/ios/app/work-log-ultimate-free-plan-log-analyze-time-tracking-made-easy/id798654796) All apps by Dr. Oliver Fox: https://appshunter.io/developer/334264533 --- *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.*