# Z21 mobile HD vs Model Train Script

The clearest difference is iOS requirement: Z21 mobile HD at 5.1.1 against Model Train Script's 18.6. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Z21 mobile HD sells 3 one-off in-app purchases and Model Train Script sells 2 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

Z21 mobile HD ships an update monthly, Model Train Script every 3 weeks. The most recent releases landed on September 18, 2026 and October 4, 2026 respectively.

## The numbers

| Metric | Z21 mobile HD | Model Train Script |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (3 ratings)](https://appshunter.io/ios/app/z21-mobile-hd/id535465008/reviews)** | — |
| Number of ratings | **3** | — |
| Positive reviews | 57.1% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 3 weeks** |
| Monetization | Free | — |
| Size | 46 MB | 46 MB |
| Requires iOS | **5.1.1** | 18.6 |
| Devices | iPad | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Modelleisenbahn GmbH](https://appshunter.io/developer/533805542) | [Arjan Pragt](https://appshunter.io/developer/1654600131) |

## What reviewers say

### Z21 mobile HD

[App page](https://appshunter.io/ios/app/z21-mobile-hd/id535465008)

Control your model train layout and locomotives directly from your iOS device. Manage your locomotive library, program digital components, and operate trains with intuitive touch controls. A demo mode is available for exploration.

**Highlights:** Connect to Z21 Digital Center, Manage locomotive libraries, Control locomotives with DCC/Motorola decoders, Program digital components, Intuitive graphic interface, Assign custom locomotive images

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| BR52 | $10.99 | one-time |
| RH 109.13 | $10.99 | one-time |
| BR103 | $10.99 | one-time |


### Model Train Script

[App page](https://appshunter.io/ios/app/model-train-script/id6444422153)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Donation for ModelTrainScript | $9.00 | one-time |
| License | $12.99 | one-time |


## Frequently asked questions

### Is Z21 mobile HD free?

Z21 mobile HD is free to download, with in-app purchases available.

### Is Model Train Script free?

Model Train Script is free to download, with in-app purchases available.

### Do Z21 mobile HD or Model Train Script have ads?

Neither Z21 mobile HD nor Model Train Script shows ads.

### Which is updated more often, Z21 mobile HD or Model Train Script?

Z21 mobile HD ships an update monthly, and Model Train Script every 3 weeks. Most recently, Z21 mobile HD was updated on September 18, 2026 and Model Train Script 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.*