# iTurbo vs StampReady

The clearest difference is in-app purchases: iTurbo at none against StampReady's 2. On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. StampReady sells 2 in-app purchases, starting at $99.99 per 3 months. iTurbo asks for nothing beyond the download.

## The numbers

| Metric | iTurbo | StampReady |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/iturbo/id314368331/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 54 months | — |
| Monetization | Free | — |
| Size | 2 MB | 29 MB |
| Requires iOS | **18.0** | 18.3 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Torbjorn Sjogren](https://appshunter.io/developer/313743954) | [Invictera](https://appshunter.io/developer/1878758866) |

## What reviewers say

### iTurbo

[App page](https://appshunter.io/ios/app/iturbo/id314368331)

This app simulates fluid dynamics by solving Navier-Stokes equations for 2D incompressible turbulence. It uses a direct numerical simulation method with Euler time stepping and Fourier space calculations for efficiency.

**Highlights:** Direct Numerical Simulation (DNS), Navier-Stokes equation solver, 2D incompressible turbulence, Euler time stepping, Fourier space calculations, Vorticity field transformation

**Features:** macOS Compatibility

**In-app purchases:** none


### StampReady

[App page](https://appshunter.io/ios/app/stampready-pe-exam-prep/id6760597963)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| StampReady Pro | $99.99 | per 3 months |
| StampReady Pro | $149.99 | per 6 months |


## Frequently asked questions

### Is iTurbo free?

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

### Is StampReady free?

StampReady is free to download, with in-app purchases available.

### Do iTurbo or StampReady have ads?

Neither iTurbo nor StampReady shows ads.

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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.*