# OffOf vs Odometer Data Observer

The clearest difference is price: Odometer Data Observer at Free against OffOf's $0.99. Odometer Data Observer also leads on update cadence (every 5 days vs every 59 months). OffOf's advantage is in-app purchases (none vs 10) and device support (5 vs 2). On ads there is nothing between them.

Odometer Data Observer is free to download; OffOf costs $0.99 up front. Odometer Data Observer sells 10 in-app purchases, starting at $2.99 per month. OffOf asks for nothing beyond the download.

OffOf ships an update every 59 months, Odometer Data Observer every 5 days. The most recent releases landed on September 22, 2026 and September 13, 2026 respectively.

## The numbers

| Metric | OffOf | Odometer Data Observer |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | **[4.6 (11 ratings)](https://appshunter.io/ios/app/offof/id883081837/reviews)** | — |
| Number of ratings | **11** | — |
| Positive reviews | 60.7% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 59 months | **Every 5 days** |
| Monetization | Free | — |
| Size | 5 MB | 4 MB |
| Requires iOS | **17.2** | 26.2 |
| Devices | **iPhone, iPad, Mac, Apple Watch, Vision Pro** | iPhone, iPad |
| Age rating | 4+ | 17+ |
| Developer | [Daeo Corp. Software](https://appshunter.io/developer/440991527) | [Sotiris Sotiriou](https://appshunter.io/developer/1885769517) |

## What reviewers say

### OffOf

[App page](https://appshunter.io/ios/app/offof/id883081837)

This app simplifies percentage calculations for shopping discounts and finding a percentage of a number. It offers a clean interface with satisfying sound and haptic feedback for a delightful user experience.

**Highlights:** Calculate percentage OFF, Calculate percentage OF, Shopping discount calculations, Mechanical keyboard sounds, Haptic feedback

**Features:** Apple Watch app

**In-app purchases:** none

**What reviewers like**

- ✨ Gorgeous design
- 👍 Simple and useful utility
- 💯 Best percentage calculator
- ✅ Does what it says
- 💡 Beautifully minimalist

**What reviewers complain about**

- ❌ Not updated
- ⚠️ Abandoned app
- 📉 No longer works
- 💔 Incompatible with iOS
- ⏳ Outdated

**Reported bugs**

- Not compatible with new iOS updates
- App no longer opens/works
- Freezes and force closes

**Requested features**

- Make it a fully functional calculator
- Update to new software/iOS versions
- Show final price after discount
- Auto clear fields on tap
- Update for X screens


### Odometer Data Observer

[App page](https://appshunter.io/ios/app/odometer-data-observer/id6760692984)

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

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 ADDITIONAL CAR (Monthly) | $2.99 | per month |
| COST MANAGEMENT (Monthly) | $2.99 | per month |
| BASIC (Monthly) | $4.99 | per month |
| 2 ADDITIONAL CARS (Monthly) | $4.99 | per month |
| 3 ADDITIONAL CARS (Monthly) | $7.99 | per month |
| 1 ADDITIONAL CAR (Yearly) | $24.99 | per year |
| COST MANAGEMENT (Yearly) | $24.99 | per year |
| BASIC (Yearly) | $49.99 | per year |
| 2 ADDITIONAL CARS (Yearly) | $49.99 | per year |
| 3 ADDITIONAL CARS (Yearly) | $79.99 | per year |


## Frequently asked questions

### Is OffOf free?

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

### Is Odometer Data Observer free?

Odometer Data Observer is free to download, with in-app purchases available.

### Do OffOf or Odometer Data Observer have ads?

Neither OffOf nor Odometer Data Observer shows ads.

### Which is updated more often, OffOf or Odometer Data Observer?

OffOf ships an update every 59 months, and Odometer Data Observer every 5 days. Most recently, OffOf was updated on September 22, 2026 and Odometer Data Observer on September 13, 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.*