# Key vs ACMP

Key and ACMP are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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

Key ships an update every 4 months, ACMP every 5 months. The most recent releases landed on June 7, 2026 and September 9, 2026 respectively.

## The numbers

| Metric | Key | ACMP |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 months** | Every 5 months |
| Monetization | Free | — |
| Size | 18 MB | 101 MB |
| Requires iOS | 17.0 | **16.0** |
| Devices | iPhone, iPod, Apple Watch | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Interflex Datensysteme GmbH](https://appshunter.io/developer/1150331434) | [Aagon GmbH](https://appshunter.io/developer/1476401885) |

## What reviewers say

### Key

[App page](https://appshunter.io/ios/app/key/id1150331435)

Transform your iPhone into a mobile ID card for convenient door access. Securely register your credentials and use your phone to open doors, leveraging advanced encrypted transfer technology.

**Highlights:** Smartphone as mobile ID, Convenient door opening, Secure credential transfer, iPhone integration, Requires Interflex software

**In-app purchases:** none


### ACMP

[App page](https://appshunter.io/ios/app/acmp/id1476401886)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Key free?

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

### Is ACMP free?

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

### Do Key or ACMP have ads?

Neither Key nor ACMP shows ads.

### Which is updated more often, Key or ACMP?

Key ships an update every 4 months, and ACMP every 5 months. Most recently, Key was updated on June 7, 2026 and ACMP on September 9, 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.*