# Battery Master 12V vs 4GIOT

The clearest difference is update cadence: Battery Master 12V at every 6 weeks against 4GIOT's every 9 months. 4GIOT's advantage is iOS requirement (13.0 vs 15.6). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Battery Master 12V ships an update every 6 weeks, 4GIOT every 9 months. The most recent releases landed on September 10, 2026 and May 14, 2026 respectively.

## The numbers

| Metric | Battery Master 12V | 4GIOT |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.4 (5 ratings)](https://appshunter.io/ios/app/battery-master-12v/id1480710112/reviews)** | — |
| Number of ratings | **5** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 6 weeks** | Every 9 months |
| Monetization | Free | — |
| Size | 39 MB | 71 MB |
| Requires iOS | 15.6 | **13.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Shenzhen Leagend Optoelectronics Co., Ltd.](https://appshunter.io/developer/6798210621) | [XiaoBo Gao](https://appshunter.io/developer/1514325028) |

## What reviewers say

### Battery Master 12V

[App page](https://appshunter.io/ios/app/battery-master-12v/id1480710112)

This tool detects and tests lead-acid batteries, assessing CCA and health. It calculates remaining battery life based on temperature and CCA data. Users can also test cranking and charging systems, with all results shareable and printable.

**Highlights:** Lead-acid battery detection, Test battery CCA and health, Calculate available use life, Test cranking system, Test charging system, Share and print test results

**Features:** macOS Compatibility

**In-app purchases:** none


### 4GIOT

[App page](https://appshunter.io/ios/app/4giot/id6736829064)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Battery Master 12V free?

Battery Master 12V is free to download, with no in-app purchases.

### Is 4GIOT free?

4GIOT is free to download, with no in-app purchases.

### Do Battery Master 12V or 4GIOT have ads?

Neither Battery Master 12V nor 4GIOT shows ads.

### Which is updated more often, Battery Master 12V or 4GIOT?

Battery Master 12V ships an update every 6 weeks, and 4GIOT every 9 months. Most recently, Battery Master 12V was updated on September 10, 2026 and 4GIOT on May 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.*