# Conversion vs Battery Testing Master

The clearest difference is review sentiment: Conversion at 61% against Battery Testing Master's 0%. Conversion also leads on in-app purchases (none vs 1) and ads (none vs shown). Battery Testing Master's advantage is price (Free vs $0.99) and rating (4.5 vs 3.0). On device support there is nothing between them.

Battery Testing Master is free to download; Conversion costs $0.99 up front. Battery Testing Master sells 1 one-off in-app purchase. Conversion asks for nothing beyond the download.

Battery Testing Master holds the better App Store score, 4.5 against 3.0. That said, the two scores are not equally well evidenced: Battery Testing Master has 28 ratings behind it against 5, so its average is the more settled of the two. Written reviews complicate that: 61% of Conversion's written reviews are positive against 0% of Battery Testing Master's, so the app with the better star average is not the one people write more warmly about.

Conversion ships an update every 2 months, Battery Testing Master every 5 days. The most recent releases landed on November 10, 2026 and November 4, 2026 respectively.

## The numbers

| Metric | Conversion | Battery Testing Master |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | [3.0 (5 ratings)](https://appshunter.io/ios/app/conversion-unit-converter/id286552073/reviews) | **[4.5 (28 ratings)](https://appshunter.io/ios/app/battery-testing-master/id6502358441/reviews)** |
| Number of ratings | 5 | **28** |
| Positive reviews | **61.0% of reviews** | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 2 months | **Every 5 days** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 2 MB | 40 MB |
| Requires iOS | 26.0 | **14.0** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Duncan Campbell](https://appshunter.io/developer/286552076) | [Nguyen Ngoc Long](https://appshunter.io/developer/1652022123) |

## What reviewers say

### Conversion

[App page](https://appshunter.io/ios/app/conversion-unit-converter/id286552073)

This utility app provides instant conversions between a wide range of units, including metric, imperial, and currency. It features live exchange rates and supports 33 languages, all within a clean, clutter-free interface.

**Highlights:** Extensive unit categories (12 categories, 96 units), Live, offline-capable currency exchange rates, Supports 33 languages and regional number formats, Modern, clutter-free interface with fluid animations, Full VoiceOver and accessibility support, No ads, analytics, or tracking

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

**In-app purchases:** none


### Battery Testing Master

[App page](https://appshunter.io/ios/app/battery-testing-master/id6502358441)

This application benchmarks the battery performance of mobile devices. It provides a comprehensive test for battery health, suitable for both new and used batteries on iOS devices.

**Highlights:** Battery benchmarking, Battery health testing, Mobile device optimization, iOS battery analysis

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove ads | $1.99 | one-time |


## Frequently asked questions

### Is Conversion free?

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

### Is Battery Testing Master free?

Battery Testing Master is free to download, with in-app purchases available.

### Which has better reviews, Conversion or Battery Testing Master?

Battery Testing Master is rated higher. Conversion averages 3.0 out of 5 from 5 ratings, while Battery Testing Master averages 4.5 from 28 ratings.

### Do Conversion or Battery Testing Master have ads?

Battery Testing Master shows ads; Conversion does not.

### Which is updated more often, Conversion or Battery Testing Master?

Conversion ships an update every 2 months, and Battery Testing Master every 5 days. Most recently, Conversion was updated on November 10, 2026 and Battery Testing Master on November 4, 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.*