# Probability Sim vs Gacha Calc

The clearest difference is in-app purchases: Gacha Calc at none against Probability Sim's 2. Gacha Calc also leads on update cadence (daily vs every 10 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Probability Sim sells 2 in-app purchases, starting at $4.99 per month. Gacha Calc asks for nothing beyond the download.

Probability Sim ships an update every 10 months, Gacha Calc daily. The most recent releases landed on October 22, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | Probability Sim | Gacha Calc |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | Yes | Yes |
| Update frequency | Every 10 months | **Daily** |
| Size | 29 MB | 36 MB |
| Requires iOS | 15.0 | **14.0.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [kota tada](https://appshunter.io/developer/1658942612) | [hyeokjin cho](https://appshunter.io/developer/1859562663) |

## What reviewers say

### Probability Sim

[App page](https://appshunter.io/ios/app/probability-sim-trillion/id6743378063)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Ad-free for 1 month | $4.99 | per month |
| Ad-free for 1 year | $49.99 | per year |


### Gacha Calc

[App page](https://appshunter.io/ios/app/gacha-calc-probability-sim/id6756255892)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Probability Sim free?

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

### Is Gacha Calc free?

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

### Do Probability Sim or Gacha Calc have ads?

Both Probability Sim and Gacha Calc show ads.

### Which is updated more often, Probability Sim or Gacha Calc?

Probability Sim ships an update every 10 months, and Gacha Calc daily. Most recently, Probability Sim was updated on October 22, 2026 and Gacha Calc on October 6, 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.*