# Battery vs Rootbly

The clearest difference is rating: Rootbly at 4.0 against Battery's 3.5. Rootbly also leads on in-app purchases (none vs 1) and update cadence (fortnightly vs monthly). Battery's advantage is ratings volume (13 vs 1) and iOS requirement (6.0 vs 16.4). On price, ads and device support there is nothing between them.

Both are free to download. Battery sells 1 one-off in-app purchase. Rootbly asks for nothing beyond the download.

Rootbly holds the better App Store score, 4.0 against 3.5. That said, the two scores are not equally well evidenced: Battery has 13 ratings behind it against 1, so its average is the more settled of the two.

Battery ships an update monthly, Rootbly fortnightly. Both last shipped on October 14, 2026.

## The numbers

| Metric | Battery | Rootbly |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.5 (13 ratings)](https://appshunter.io/ios/app/battery/id398981675/reviews) | **[4.0 (1 ratings)](https://appshunter.io/ios/app/rootbly-ai-subtitle/id6761355562/reviews)** |
| Number of ratings | **13** | 1 |
| Positive reviews | 29.4% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Monthly | **Fortnightly** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 4 MB | 41 MB |
| Requires iOS | **6.0** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Orgajja Co Ltd](https://appshunter.io/developer/368955015) | [Byeongsu KIM](https://appshunter.io/developer/1827219380) |

## What reviewers say

### Battery

[App page](https://appshunter.io/ios/app/battery/id398981675)

Explore the fundamental principles of electrochemical cells and their conversion of chemical to electrical energy. Understand the distinction between disposable primary batteries and rechargeable secondary batteries, and their diverse applications.

**Highlights:** Electrochemical cell principles, Chemical to electrical energy conversion, Primary (disposable) batteries, Secondary (rechargeable) batteries, Applications of batteries

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Upgrade | $0.99 | one-time |

**What reviewers like**

- 🔋 Basic battery info provided
- 👍 Simple and not elaborate
- 👍 Useful for iPod Touch
- 👍 Accurate battery percentage
- 👍 Helpful for knowing battery level

**What reviewers complain about**

- 👎 Very basic information
- 👎 Forced to download other apps
- 👎 Too many ads
- 👎 Inaccurate battery percentage
- 👎 App crashes frequently

**Reported bugs**

- Crashes on opening
- Opens ads and redirects
- Lagging out device
- Cannot use all functions without download
- Doesn't open

**Requested features**

- Remove ads
- Upgrade option to remove ads
- Add more functions
- Remove slot machine game prompt
- Fix crashing issues


### Rootbly

[App page](https://appshunter.io/ios/app/rootbly-ai-subtitle/id6761355562)

Watch foreign YouTube videos with AI-generated translated subtitles in real-time. Paste a URL to get instant subtitles in your preferred language, with options to adjust sync, size, and view original text.

**Highlights:** AI subtitle translation, 15 languages supported, Real-time subtitle display, Subtitle sync adjustment, Customizable subtitle size, YouTube search and browsing, Job progress tracking

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

**In-app purchases:** none


## Frequently asked questions

### Is Battery free?

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

### Is Rootbly free?

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

### Which has better reviews, Battery or Rootbly?

Rootbly is rated higher. Battery averages 3.5 out of 5 from 13 ratings, while Rootbly averages 4.0 from 1 ratings.

### Do Battery or Rootbly have ads?

Neither Battery nor Rootbly shows ads.

### Which is updated more often, Battery or Rootbly?

Battery ships an update monthly, and Rootbly fortnightly. Most recently, Battery was updated on October 14, 2026 and Rootbly on October 14, 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.*