# IngSoft InterWatt (eIAM) vs RETTERAlarm NAVIS

The clearest difference is iOS requirement: RETTERAlarm NAVIS at 13.0 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.

IngSoft InterWatt (eIAM) ships an update fortnightly, RETTERAlarm NAVIS every 3 weeks. The most recent releases landed on October 30, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | IngSoft InterWatt (eIAM) | RETTERAlarm NAVIS |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 3 weeks |
| Size | 51 MB | 61 MB |
| Requires iOS | 15.6 | **13.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [IngSoft GmbH](https://appshunter.io/developer/945284664) | [Sascha Radermacher](https://appshunter.io/developer/528345987) |

## What reviewers say

### IngSoft InterWatt (eIAM)

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

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

**In-app purchases:** none


### RETTERAlarm NAVIS

[App page](https://appshunter.io/ios/app/retteralarm-navis/id6760187406)

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

**In-app purchases:** none


## Frequently asked questions

### Is IngSoft InterWatt (eIAM) free?

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

### Is RETTERAlarm NAVIS free?

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

### Do IngSoft InterWatt (eIAM) or RETTERAlarm NAVIS have ads?

Neither IngSoft InterWatt (eIAM) nor RETTERAlarm NAVIS shows ads.

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

IngSoft InterWatt (eIAM) ships an update fortnightly, and RETTERAlarm NAVIS every 3 weeks. Most recently, IngSoft InterWatt (eIAM) was updated on October 30, 2026 and RETTERAlarm NAVIS on October 31, 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.*