# HP 15c Calculator vs Plus42

The clearest difference is update cadence: Plus42 at weekly against HP 15c Calculator's every 16 months. Plus42 also leads on review sentiment (92% vs 68%) and price ($9.99 vs $14.99). On rating, ratings volume, ads and in-app purchases there is nothing between them.

HP 15c Calculator costs $14.99 and Plus42 $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 4.8 for HP 15c Calculator against 4.9 for Plus42. Both are backed by a comparable volume of ratings — 219 and 79 respectively. Written reviews are what separate them: 68% of HP 15c Calculator's written reviews are positive against 92% of Plus42's.

HP 15c Calculator ships an update every 16 months, Plus42 weekly. The most recent releases landed on November 1, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | HP 15c Calculator | Plus42 |
| --- | --- | --- |
| Price | $14.99 | **$9.99** |
| Rating | [4.8 (219 ratings)](https://appshunter.io/ios/app/hp-15c-calculator/id503720774/reviews) | **[4.9 (79 ratings)](https://appshunter.io/ios/app/plus42/id1597963622/reviews)** |
| Number of ratings | **219** | 79 |
| Positive reviews | 68.2% of reviews | **92.3% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 16 months | **Weekly** |
| Monetization | Paid | **Free** |
| Best chart rank | — | **#119** |
| Size | 45 MB | 11 MB |
| Requires iOS | 15.6 | **15.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [MORAVIA Consulting, spol. s r.o.](https://appshunter.io/developer/1673101600) | [Thomas Okken](https://appshunter.io/developer/337692632) |

## What reviewers say

### HP 15c Calculator

[App page](https://appshunter.io/ios/app/hp-15c-calculator/id503720774)

Experience the official emulator of the legendary HP 15c scientific calculator. This app offers a redesigned interface and modern look while preserving the precision and reliability of the original. It features RPN input, matrix calculations, complex functions, and numerical integration for professionals and students.

**Highlights:** Official HP 15c emulator, RPN (Reverse Polish Notation), Matrix calculations, Complex functions, Numerical integration, Programmable (448 lines)

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 🚀 Excellent emulation of original HP 15C
- 👍 Faithful reproduction of classic calculator
- 👍 Includes original manual
- 👍 Works just like the real thing
- 👍 Vertical layout with key features

**What reviewers complain about**

- 🐛 Display issues in portrait mode
- 🐛 Bugs with programming and trig functions
- 🔇 Loud button click sound
- 💰 Expensive for an app

**Reported bugs**

- Numbers not aligned in display window
- Display flashing after running programs
- Incompatibility with latest iOS versions

**Requested features**

- Copy and paste functionality
- Ability to change calculator models
- Option to disable button click sound
- Better support for larger iPhone screens


### Plus42

[App page](https://appshunter.io/ios/app/plus42/id1597963622)

**Currently charting:** #119 Top Paid · Utilities (US App Store)

This advanced scientific calculator simulates the classic HP-42S RPN calculator with enhanced features. It offers algebraic expressions, unit conversions, directories for storage, a larger resizable display, financial functions, and 2D plotting with integral and root finding.

**Highlights:** HP-42S RPN calculator simulation, Algebraic expressions, Attached units and conversions, Program and variable directories, Resizable 8-row, 22-column display, Time value of money and amortization, 2D function plotting with zoom and pan

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is HP 15c Calculator free?

HP 15c Calculator costs $14.99, with no in-app purchases.

### Is Plus42 free?

Plus42 costs $9.99, with no in-app purchases.

### Which has better reviews, HP 15c Calculator or Plus42?

Plus42 is rated higher. HP 15c Calculator averages 4.8 out of 5 from 219 ratings, while Plus42 averages 4.9 from 79 ratings.

### Do HP 15c Calculator or Plus42 have ads?

Neither HP 15c Calculator nor Plus42 shows ads.

### Which is updated more often, HP 15c Calculator or Plus42?

HP 15c Calculator ships an update every 16 months, and Plus42 weekly. Most recently, HP 15c Calculator was updated on November 1, 2026 and Plus42 on October 30, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*