# Units vs ChangeUnits2

The clearest difference is price: Units at Free against ChangeUnits2's $0.99. Units also leads on ratings volume (150 vs 1) and iOS requirement (13.5 vs 15.6). ChangeUnits2's advantage is rating (5.0 vs 3.6) and in-app purchases (none vs 3). On update cadence and device support there is nothing between them.

Units is free to download; ChangeUnits2 costs $0.99 up front. Units sells 3 one-off in-app purchases. ChangeUnits2 asks for nothing beyond the download.

ChangeUnits2 holds the better App Store score, 5.0 against 3.6. That said, the two scores are not equally well evidenced: Units has 150 ratings behind it against 1, so its average is the more settled of the two.

Units ships an update monthly, ChangeUnits2 every 4 weeks. The most recent releases landed on September 25, 2026 and June 1, 2026 respectively.

## The numbers

| Metric | Units | ChangeUnits2 |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| Rating | [3.6 (150 ratings)](https://appshunter.io/ios/app/units-pro-unit-converter/id284574017/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/changeunits2/id1661260714/reviews)** |
| Number of ratings | **150** | 1 |
| Positive reviews | 60.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Monthly | **Every 4 weeks** |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 2 MB | 17 MB |
| Requires iOS | **13.5** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Homegrown Software Ltd](https://appshunter.io/developer/406645730) | [Jack McCormack](https://appshunter.io/developer/1658121467) |

## What reviewers say

### Units

[App page](https://appshunter.io/ios/app/units-pro-unit-converter/id284574017)

Easily convert between hundreds of units across 43 categories, including currency with daily updated rates. Customize your workflow by hiding or reordering units and categories.

**Highlights:** Hundreds of units across 43 categories, Daily updated currency exchange rates, Hide unused units, Reorder units and categories, Universal app support (iPhone, iPod touch, iPad)

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Small Tip | $0.99 | one-time |
| Medium Tip | $2.99 | one-time |
| Large Tip | $4.99 | one-time |

**What reviewers like**

- 🚀 Efficient and fast conversions
- 👍 Comprehensive list of units
- 🔍 Customizable unit selection
- 💰 Free app with optional paid version
- 🔧 Useful for engineering and technical work

**What reviewers complain about**

- 🐛 Crashes and stability issues
- 🕰️ Outdated currency conversion rates
- 🔍 Too many unit categories, hard to navigate
- 💰 Ads in free version
- 📏 Ruler feature not accurate on some devices

**Reported bugs**

- Crashes when clearing input fields
- Numerical keypad covers conversion results
- Incompatibility issues with newer iOS versions
- Ruler measurements not accurate on all devices

**Requested features**

- Add nautical units (miles, knots)
- Improve currency conversion accuracy and updates
- Allow customization of visible unit categories
- Add more clothing/shoe size conversions
- Improve user interface and search functionality


### ChangeUnits2

[App page](https://appshunter.io/ios/app/changeunits2/id1661260714)

This powerful utility app offers lightning-fast and accurate unit conversions for a wide range of needs. It includes advanced math functions, currency exchange, time zone tracking, and even chemical equation balancing. Designed for professionals and everyday users alike, it works offline and remembers your last calculations.

**Highlights:** Extreme speed and accuracy, Offline functionality, Currency exchange converter, Global time zone tracking, Advanced math functions, Chemical equation balancing, Last 33 calculations remembered

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Units free?

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

### Is ChangeUnits2 free?

ChangeUnits2 costs $0.99, with no in-app purchases.

### Which has better reviews, Units or ChangeUnits2?

ChangeUnits2 is rated higher. Units averages 3.6 out of 5 from 150 ratings, while ChangeUnits2 averages 5.0 from 1 ratings.

### Do Units or ChangeUnits2 have ads?

Units shows ads; ChangeUnits2 does not.

### Which is updated more often, Units or ChangeUnits2?

Units ships an update monthly, and ChangeUnits2 every 4 weeks. Most recently, Units was updated on September 25, 2026 and ChangeUnits2 on June 1, 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.*