# iUnit Measurement Conversion vs SaferCar

The clearest difference is review sentiment: iUnit Measurement Conversion at 100% against SaferCar's 21%. iUnit Measurement Conversion also leads on rating (3.7 vs 2.9) and iOS requirement (9.0 vs 13.0). SaferCar's advantage is price (Free vs $2.99) and update cadence (every 6 weeks vs every 48 months). On ads, in-app purchases and device support there is nothing between them.

SaferCar is free to download; iUnit Measurement Conversion costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

iUnit Measurement Conversion holds the better App Store score, 3.7 against 2.9. That said, the two scores are not equally well evidenced: SaferCar has 114 ratings behind it against 6, so its average is the more settled of the two. Written reviews point the same way: 100% of iUnit Measurement Conversion's written reviews are positive against 21% of SaferCar's.

iUnit Measurement Conversion ships an update every 48 months, SaferCar every 6 weeks. The most recent releases landed on September 17, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | iUnit Measurement Conversion | SaferCar |
| --- | --- | --- |
| Price | $2.99 | **Free** |
| Rating | **[3.7 (6 ratings)](https://appshunter.io/ios/app/iunit-measurement-conversion/id305448108/reviews)** | [2.9 (114 ratings)](https://appshunter.io/ios/app/safercar/id1526869558/reviews) |
| Number of ratings | 6 | **114** |
| Positive reviews | **100.0% of reviews** | 20.8% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 48 months | **Every 6 weeks** |
| Monetization | Paid | **Free** |
| Size | 2 MB | 71 MB |
| Requires iOS | **9.0** | 13.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Black Cat Systems](https://appshunter.io/developer/301047032) | [NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION](https://appshunter.io/developer/593086233) |

## What reviewers say

### iUnit Measurement Conversion

[App page](https://appshunter.io/ios/app/iunit-measurement-conversion/id305448108)

Easily convert between over 1650 units across 57 diverse categories. This powerful yet user-friendly application provides quick and accurate conversions for a wide range of measurements.

**Highlights:** 1650 units conversion, 57 categories, Easy to use interface, Quick conversions, Supports iPhone, iPad, iPod

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

**In-app purchases:** none


### SaferCar

[App page](https://appshunter.io/ios/app/safercar/id1526869558)

Stay informed about automotive safety recalls directly from the official source. Enter your vehicle's VIN or details about tires and car seats to receive background notifications for any safety recalls affecting your owned equipment. Access NHTSA's 5-Star Safety Ratings and car seat tools.

**Highlights:** Vehicle recall notifications, VIN entry for multiple vehicles, Recall alerts for tires and car seats, NHTSA 5-Star Safety Ratings, Car seat installation tools, Background operation for alerts

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- ✅ App recognizes valid VINs
- ✅ Recall information is useful
- ✅ Barcode scanning works sometimes
- ✅ App updates quickly
- ✅ Good for tracking recalls

**What reviewers complain about**

- ❌ VIN lookup errors
- ❌ Vehicle selection limited
- ❌ App crashes frequently
- ❌ Requires app to be open
- ❌ Poor user interface

**Reported bugs**

- VIN Lookup Error
- App crashes on opening
- App freezes after prompts
- App won't open with iOS 14
- App flickers and disappears

**Requested features**

- Allow searching for any vehicle recalls, not just owned ones
- Remove vehicle tracking limit
- Allow users to write notes for vehicles
- Adjust notification times
- Improve VIN barcode auto-identification


## Frequently asked questions

### Is iUnit Measurement Conversion free?

iUnit Measurement Conversion costs $2.99, with no in-app purchases.

### Is SaferCar free?

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

### Which has better reviews, iUnit Measurement Conversion or SaferCar?

iUnit Measurement Conversion is rated higher. iUnit Measurement Conversion averages 3.7 out of 5 from 6 ratings, while SaferCar averages 2.9 from 114 ratings.

### Do iUnit Measurement Conversion or SaferCar have ads?

Neither iUnit Measurement Conversion nor SaferCar shows ads.

### Which is updated more often, iUnit Measurement Conversion or SaferCar?

iUnit Measurement Conversion ships an update every 48 months, and SaferCar every 6 weeks. Most recently, iUnit Measurement Conversion was updated on September 17, 2026 and SaferCar on October 17, 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.*