# Kalkyl vs TRN Audio

The clearest difference is in-app purchases: TRN Audio at none against Kalkyl's 1. TRN Audio also leads on update cadence (every 4 days vs every 5 weeks) and iOS requirement (13.0 vs 15.6). Kalkyl's advantage is device support (4 vs 2). On price and ads there is nothing between them.

Both are free to download. Kalkyl sells 1 in-app purchase, starting at $4.99 per year. TRN Audio asks for nothing beyond the download.

Kalkyl ships an update every 5 weeks, TRN Audio every 4 days. The most recent releases landed on September 28, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | Kalkyl | TRN Audio |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.5 (714 ratings)](https://appshunter.io/ios/app/kalkyl/id519933025/reviews)** | — |
| Number of ratings | **714** | — |
| Positive reviews | 74.7% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 5 weeks | **Every 4 days** |
| Monetization | Freemium | — |
| Size | 4 MB | 34 MB |
| Requires iOS | 15.6 | **13.0** |
| Devices | **iPhone, iPad, iPod, Vision Pro** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [nordic io](https://appshunter.io/developer/519933028) | [娟 伍](https://appshunter.io/developer/6793145741) |

## What reviewers say

### Kalkyl

[App page](https://appshunter.io/ios/app/kalkyl/id519933025)

A powerful and intuitive calculator designed for speed and ease of use. Features include collaboration, haptic feedback, and advanced input methods like keyboard trackpad mode. Offers basic graphing and localized number formatting for a seamless user experience.

**Highlights:** Optimized for quick calculations, Collaborate on documents, Intuitive design with haptic feedback, Keyboard trackpad and pointer interactions, Basic graphing capabilities, Localized number formatting, Undo and Redo support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Kalkyl Pro | $4.99 | per year |

**What reviewers like**

- 🚀 Efficient and fast
- 👍 Intuitive and simple interface
- 🔒 No ads or in-app purchases
- 🎨 Beautiful design
- 🔢 Useful graphing and calculation features

**What reviewers complain about**

- 🐛 Occasional crashes or bugs
- 💡 Lack of clear/reset button
- 💡 Missing history or memory functions
- 💡 Difficulty controlling graphing view

**Reported bugs**

- Crashes on launch for some users
- Graphing issues with certain equations
- Incorrect results for some calculations

**Requested features**

- Add a clear/reset button
- Implement calculation history and memory functions
- Improve graphing controls and zooming
- Add support for more mathematical functions (e.g. factorials, fractions)
- Provide an option for independent dark mode


### TRN Audio

[App page](https://appshunter.io/ios/app/trn-audio/id6798907124)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Kalkyl free?

Kalkyl is free to download, with in-app purchases available.

### Is TRN Audio free?

TRN Audio is free to download, with no in-app purchases.

### Do Kalkyl or TRN Audio have ads?

Neither Kalkyl nor TRN Audio shows ads.

### Which is updated more often, Kalkyl or TRN Audio?

Kalkyl ships an update every 5 weeks, and TRN Audio every 4 days. Most recently, Kalkyl was updated on September 28, 2026 and TRN Audio on September 18, 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.*