# BATT SYNC vs EM3720

The clearest difference is iOS requirement: EM3720 at 11.0 against BATT SYNC's 15.6. On price, update cadence, ads and in-app purchases there is nothing between them.

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

BATT SYNC ships an update every 6 months, EM3720 every 4 months. The most recent releases landed on September 21, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | BATT SYNC | EM3720 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 6 months | **Every 4 months** |
| Size | 34 MB | 6 MB |
| Requires iOS | 15.6 | **11.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 17+ |
| Developer | [DHC Specialty Corp.](https://appshunter.io/developer/1130832649) | [ZHANGZHOU EASTERN INTELLIGENT METER CO., LTD.](https://appshunter.io/developer/1064839954) |

## What reviewers say

### BATT SYNC

[App page](https://appshunter.io/ios/app/batt-sync/id1286964635)

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

**In-app purchases:** none


### EM3720

[App page](https://appshunter.io/ios/app/em3720/id1376380656)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is BATT SYNC free?

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

### Is EM3720 free?

EM3720 is free to download, with no in-app purchases.

### Do BATT SYNC or EM3720 have ads?

Neither BATT SYNC nor EM3720 shows ads.

### Which is updated more often, BATT SYNC or EM3720?

BATT SYNC ships an update every 6 months, and EM3720 every 4 months. Most recently, BATT SYNC was updated on September 21, 2026 and EM3720 on September 18, 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.*