# Probability vs Rex Roulette Predictor

The clearest difference is in-app purchases: Probability at none against Rex Roulette Predictor's 1. Probability also leads on iOS requirement (9.0 vs 12.0). Rex Roulette Predictor's advantage is update cadence (daily vs every 18 months). On price, ads and device support there is nothing between them.

Both are free to download. Rex Roulette Predictor sells 1 in-app purchase, starting at $15.00 per month. Probability asks for nothing beyond the download.

Probability ships an update every 18 months, Rex Roulette Predictor daily. The most recent releases landed on October 6, 2026 and October 3, 2026 respectively.

## The numbers

| Metric | Probability | Rex Roulette Predictor |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 18 months | **Daily** |
| Size | 1 MB | 32 MB |
| Requires iOS | **9.0** | 12.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 17+ |
| Developer | [domesticusdevelop](https://appshunter.io/developer/373834594) | [ismail kirmizigul](https://appshunter.io/developer/1760187460) |

## What reviewers say

### Probability

[App page](https://appshunter.io/ios/app/probability-dd/id1451460705)

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

**In-app purchases:** none


### Rex Roulette Predictor

[App page](https://appshunter.io/ios/app/rex-roulette-predictor/id6612039110)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Rex Roulette Predictor Pro | $15.00 | per month |


## Frequently asked questions

### Is Probability free?

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

### Is Rex Roulette Predictor free?

Rex Roulette Predictor is free to download, with in-app purchases available.

### Do Probability or Rex Roulette Predictor have ads?

Neither Probability nor Rex Roulette Predictor shows ads.

### Which is updated more often, Probability or Rex Roulette Predictor?

Probability ships an update every 18 months, and Rex Roulette Predictor daily. Most recently, Probability was updated on October 6, 2026 and Rex Roulette Predictor on October 3, 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.*