# Unit Converter Calculator Pro vs Drift

The clearest difference is in-app purchases: Drift at none against Unit Converter Calculator Pro's 4. Drift also leads on update cadence (weekly vs monthly). Unit Converter Calculator Pro's advantage is device support (4 vs 1) and iOS requirement (13.0 vs 17.6). On price and ads there is nothing between them.

Both are free to download. Unit Converter Calculator Pro sells 4 one-off in-app purchases. Drift asks for nothing beyond the download.

Unit Converter Calculator Pro ships an update monthly, Drift weekly. The most recent releases landed on September 27, 2026 and September 25, 2026 respectively.

## The numbers

| Metric | Unit Converter Calculator Pro | Drift |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (977 ratings)](https://appshunter.io/ios/app/unit-converter-calculator-pro/id1343845631/reviews)** | — |
| Number of ratings | **977** | — |
| Positive reviews | 76.2% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | Yes |
| Update frequency | Monthly | **Weekly** |
| Monetization | Free with in-app purchases | — |
| Size | 37 MB | 11 MB |
| Requires iOS | **13.0** | 17.6 |
| Devices | **iPhone, iPad, iPod, Apple Watch** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Rome Rock LLC](https://appshunter.io/developer/1190244007) | [Shih-Kung Chen](https://appshunter.io/developer/871339068) |

## What reviewers say

### Unit Converter Calculator Pro

[App page](https://appshunter.io/ios/app/unit-converter-calculator-pro/id1343845631)

Easily convert between metric and imperial units for a wide range of measurements including area, speed, temperature, and weight. Supports scientific prefixes and offers a history of your conversions. No internet connection required.

**Highlights:** Metric to Imperial unit conversion, Imperial to Metric unit conversion, Area, speed, temperature, volume, weight conversions, Scientific prefixes support, Conversion history, Offline functionality

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads & Unlock Themes | $2.99 | one-time |
| Remove Ads & Unlock Themes 1 | $4.99 | one-time |
| Remove Ads & Unlock Themes 2 | $6.99 | one-time |
| Remove Ads & Unlock Themes 3 | $9.99 | one-time |

**What reviewers like**

- 🚀 Easy & accurate
- 🚀 Excellent Tool
- 👍 Goog for social
- 👍 Excelente para mi trabajo
- 👍 Sencillez

**What reviewers complain about**

- 👎 Hard to use interface
- 👎 Lacks pressure units
- 👎 No reverse button
- 👎 Metric to imperial format not user-friendly

**Reported bugs**

- 🐛 Changing to something else

**Requested features**

- 💡 Favorite conversations
- 💡 Color-coded sections
- 💡 Money conversion


### Drift

[App page](https://appshunter.io/ios/app/drift-secrets-in-code/id6753609055)

**In-app purchases:** none


## Frequently asked questions

### Is Unit Converter Calculator Pro free?

Unit Converter Calculator Pro is free to download, with in-app purchases available.

### Is Drift free?

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

### Do Unit Converter Calculator Pro or Drift have ads?

Both Unit Converter Calculator Pro and Drift show ads.

### Which is updated more often, Unit Converter Calculator Pro or Drift?

Unit Converter Calculator Pro ships an update monthly, and Drift weekly. Most recently, Unit Converter Calculator Pro was updated on September 27, 2026 and Drift on September 25, 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.*