# RPN 3D Touch

> A calculator app that uses Reverse Polish Notation (RPN) for mathematical input. (iPhone/iPad app by HPR-Solutions.)

- Source: https://appshunter.io/ios/app/rpn-3d-touch/id1038850316 (this page in markdown: same URL + `.md`)
- Developer: [HPR-Solutions](https://appshunter.io/developer/362297746)
- Category: Productivity, Education
- Price: $0.99
- Age rating: 4+
- Requires: iOS 13.0 · 1 MB
- Languages: English
- Released: 2016-03-19
- Data updated: 2026-06-10
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/rpn-3d-touch/id1038850316/reviews.md

## What is RPN 3D Touch?

A calculator using rpn (reverse polish notation)

Wikipedia:

[https://en.wikipedia.org/wiki/Reverse_Polish_notation]

Reverse Polish notation (RPN) is a mathematical notation in which every operator follows all of its operands, in contrast to Polish notation (PN), which puts the operator in the prefix position. It is also known as postfix notation and is parenthesis-free as long as operator arities are fixed. The description "Polish" refers to the nationality of logician Jan Łukasiewicz,[1] who invented (prefix) Polish notation in the 1920s.[2][3]

The reverse Polish scheme was proposed in 1954 by Burks, Warren, and Wright[4] and was independently reinvented by F. L. Bauer and E. W. Dijkstra in the early 1960s to reduce computer memory access and utilize the stack to evaluate expressions. The algorithms and notation for this scheme were extended by Australian philosopher and computer scientist Charles Hamblin in the mid-1950s.[5][6]

During the 1970s and 1980s, RPN was well-known to many calculator users, as Hewlett-Packard used it in their pioneering 9100A[7] and HP-35 scientific calculators, the succeeding Voyager series - and also the "cult" HP-12C financial calculator.[8]

In computer science, postfix notation is often used in stack-based and concatenative programming languages. It is also common in dataflow and pipeline-based systems, including Unix pipelines.

Most of what follows is about binary operators. A unary operator for which the reverse Polish notation is the general convention is the factorial.

## Key features

- Reverse Polish Notation (RPN) input
- Parenthesis-free calculations
- Inspired by historical RPN calculators
- Suitable for iPhone and iPad

## Recent user reviews (1 of 1)

All indexed reviews: https://appshunter.io/ios/app/rpn-3d-touch/id1038850316/reviews.md

### 5/5 — Excellente ergonomie

*2017-05-30*

Excellente surprise que cette calculatrice RPN, simple mais complète et bien mieux pensée que les innombrables clones HP inadaptés à la taille des écrans iPhone. 

Les touches sont à la bonne taille et l'interface, plus élaborée qu'il n'y paraît, est le point fort de cette App car elle est très lisible et cohérente, avec des codes de couleurs définissant des groupes de touches. 

Utilisation judicieuse du 3D Touch pour obtenir, au final, une ergonomie au goût du jour et tout à fait dans l'esprit iOS. 5 étoiles.

## Frequently asked questions about RPN 3D Touch

### What is RPN 3D Touch?

RPN 3D Touch is a calculator application that uses Reverse Polish Notation (RPN) for input. This method places operators after their operands, allowing for parenthesis-free calculations and a potentially more efficient workflow for some users.

### How much does RPN 3D Touch cost?

RPN 3D Touch is a paid application, available for a one-time purchase of $0.99. This price grants you full access to its RPN calculation features without any additional in-app purchases or subscriptions.

### Does RPN 3D Touch have ads?

No, RPN 3D Touch is ad-free. As a paid application, it does not contain advertisements, ensuring an uninterrupted user experience for all calculations.

### What devices is RPN 3D Touch compatible with?

RPN 3D Touch is designed for Apple devices and is supported on iPhone, iPad, and iPod. Its interface is optimized for these platforms, offering a seamless experience across your Apple ecosystem.

### When was RPN 3D Touch last updated?

The latest version of RPN 3D Touch, version 1.5, was released on October 2, 2021. This indicates the app has received updates since its initial release in 2016, suggesting ongoing support from the developer.

### What is the age rating for RPN 3D Touch?

RPN 3D Touch has an age rating of 4+. This rating suggests the app is suitable for users of all ages, with no content deemed inappropriate for younger audiences.

### Can I use RPN 3D Touch offline?

Yes, RPN 3D Touch functions as a standalone calculator and does not require an internet connection to perform calculations. You can use its RPN features anytime, anywhere, without needing to be online.

## Version history (last 5 releases)

### 1.5 — 2021-10-02

Added iOS15 support

### 1.4 — 2021-02-04

Bugfixes, UI improvements

### 1.3 — 2019-10-02

Added some changes for iOS 13 and dark mode

### 1.2 — 2017-10-23

iPhoneX upgrade and some layout tweaks.

### 1.1 — 2016-03-19

No release notes.

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All apps by HPR-Solutions: https://appshunter.io/developer/362297746

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*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.*