# EM3720 vs MDA831 Dynamic

The clearest difference is update cadence: MDA831 Dynamic at every 2 months against EM3720's every 4 months. 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.

EM3720 ships an update every 4 months, MDA831 Dynamic every 2 months. The most recent releases landed on October 5, 2026 and October 4, 2026 respectively.

## The numbers

| Metric | EM3720 | MDA831 Dynamic |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 2 months** |
| Size | 6 MB | 4 MB |
| Requires iOS | **11.0** | 12.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 17+ | 4+ |
| Developer | [ZHANGZHOU EASTERN INTELLIGENT METER CO., LTD.](https://appshunter.io/developer/1064839954) | [杏生 卢](https://appshunter.io/developer/1094592555) |

## What reviewers say

### EM3720

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

**Features:** macOS Compatibility

**In-app purchases:** none


### MDA831 Dynamic

[App page](https://appshunter.io/ios/app/mda831-dynamic/id1598691124)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is EM3720 free?

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

### Is MDA831 Dynamic free?

MDA831 Dynamic is free to download, with no in-app purchases.

### Do EM3720 or MDA831 Dynamic have ads?

Neither EM3720 nor MDA831 Dynamic shows ads.

### Which is updated more often, EM3720 or MDA831 Dynamic?

EM3720 ships an update every 4 months, and MDA831 Dynamic every 2 months. Most recently, EM3720 was updated on October 5, 2026 and MDA831 Dynamic on October 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.*