Units vs Studio PDF
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Units
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.
- Extensive unit conversions
- Multiple currency support
- Easy and clear handling
- Converts length, mass, volume
- Supports speed, area, pressure
- Converts time and temperature
Read full descriptionHide full description
Unit converter with many different units of measurement and currencies. Very easy handling. Clearly arranged. The most important units are amongst others: - Currencies: United States dollar, Euro, Japanese yen, Pound sterling - Length: Mile, kilometer, meter, inch - Mass: Kilogram, pound, ounce, gram - Volume: Liter, gallon (several) - Speed - Area - Units of information - Pressure - Power - Time - Temperature Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Studio PDF
Read full descriptionHide full description
Studio PDF: A powerful toolbox, right in your pocket. Studio PDF is the ideal tool for handling your documents with ease and security. Unlike online alternatives, our app processes all your files locally on your iPhone. Your documents never leave your device: no servers, no cloud, total privacy. Why choose Studio PDF? Experience absolute privacy with no account required and zero data collection. Our native interface is designed specifically for iOS to ensure smooth performance, even with heavy documents. You get essential tools in one secure and elegant location. Your essential tools: Our page organizer allows you to reorder, rotate, or delete pages instantly with a single gesture. You can also merge multiple PDF files into one clean and structured document. For your security, add strong passwords to protect sensitive data from unauthorized access. Upgrade to the Pro version for unlimited access to merging and protection features, and enjoy a premium experience.
Screenshots
Verdict
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.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
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.
| Parameter | Units | Studio PDF |
|---|---|---|
| Price | Free | Free |
| Rating | 4.9 (261 ratings) — better | — |
| Positive reviews | 45.5% of reviews | — |
| Number of ratings | 261 — better | — |
| Update frequency | Every 5 weeks | Every 3 days — better |
| Ads | No | No |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone, iPad, iPod, Mac — better | iPhone |
| Requires iOS | 15.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 3 MB | 2 MB |
| Age rating | 4+ | 4+ |
| Developer | Andreas Maier | Simon DECAESTECKER |
In-app purchases
Units
- Monthly7 Days trial$0.991 Month
- Yearly7 Days trial$4.991 Year
- One time purchase$9.99
Studio PDF
- Studio PDF Pro - Lifetime$3.99
