# Units vs Studio PDF

The clearest difference is update cadence: Studio PDF at every 3 days against Units's every 5 weeks. Units's advantage is device support (4 vs 1) and iOS requirement (15.0 vs 17.0). On price, ads and in-app purchases there is nothing between them.

Both are free to download. Units sells 3 in-app purchases, starting at $0.99 per month and Studio PDF sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Units ships an update every 5 weeks, Studio PDF every 3 days. The most recent releases landed on September 23, 2026 and September 21, 2026 respectively.

## The numbers

| Metric | Units | Studio PDF |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.9 (261 ratings)](https://appshunter.io/ios/app/units-unit-converter/id1527329982/reviews)** | — |
| Number of ratings | **261** | — |
| Positive reviews | 45.5% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 5 weeks | **Every 3 days** |
| Monetization | Free with in-app purchases | — |
| Size | 3 MB | 2 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Andreas Maier](https://appshunter.io/developer/454364359) | [Simon DECAESTECKER](https://appshunter.io/developer/1895526351) |

## What reviewers say

### Units

[App page](https://appshunter.io/ios/app/units-unit-converter/id1527329982)

Easily convert between a wide range of measurement units and currencies. Features a clear and simple interface for quick conversions of length, mass, volume, speed, and more. Supports popular currencies and common units for everyday use.

**Highlights:** Extensive unit conversions, Multiple currency support, Easy and clear handling, Converts length, mass, volume, Supports speed, area, pressure, Converts time and temperature

**Features:** Family Sharing, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly | $0.99 | per month |
| Yearly | $4.99 | per year |
| One time purchase | $9.99 | one-time |


### Studio PDF

[App page](https://appshunter.io/ios/app/studio-pdf-local-toolbox/id6763853124)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Studio PDF Pro - Lifetime | $3.99 | one-time |


## Frequently asked questions

### Is Units free?

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

### Is Studio PDF free?

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

### Do Units or Studio PDF have ads?

Neither Units nor Studio PDF shows ads.

### Which is updated more often, Units or Studio PDF?

Units ships an update every 5 weeks, and Studio PDF every 3 days. Most recently, Units was updated on September 23, 2026 and Studio PDF on September 21, 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.*