# Z vs IngSoft InterWatt (eIAM)

The clearest difference is iOS requirement: Z at 12.0 against IngSoft InterWatt (eIAM)'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.

Z ships an update every 2 weeks, IngSoft InterWatt (eIAM) fortnightly. The most recent releases landed on September 14, 2026 and July 27, 2026 respectively.

## The numbers

| Metric | Z | IngSoft InterWatt (eIAM) |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 2 weeks** | Fortnightly |
| Size | 21 MB | 51 MB |
| Requires iOS | **12.0** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [EIBROM GmbH](https://appshunter.io/developer/478284408) | [IngSoft GmbH](https://appshunter.io/developer/945284664) |

## What reviewers say

### Z

[App page](https://appshunter.io/ios/app/z-control-v1/id1457959286)

**In-app purchases:** none


### IngSoft InterWatt (eIAM)

[App page](https://appshunter.io/ios/app/ingsoft-interwatt-eiam/id6740481986)

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

**In-app purchases:** none


## Frequently asked questions

### Is Z free?

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

### Is IngSoft InterWatt (eIAM) free?

IngSoft InterWatt (eIAM) is free to download, with no in-app purchases.

### Do Z or IngSoft InterWatt (eIAM) have ads?

Neither Z nor IngSoft InterWatt (eIAM) shows ads.

### Which is updated more often, Z or IngSoft InterWatt (eIAM)?

Z ships an update every 2 weeks, and IngSoft InterWatt (eIAM) fortnightly. Most recently, Z was updated on September 14, 2026 and IngSoft InterWatt (eIAM) on July 27, 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.*