# Function Fitter vs QuantumPass

The clearest difference is in-app purchases: Function Fitter at none against QuantumPass's 3. Function Fitter also leads on update cadence (monthly vs every 10 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. QuantumPass sells 3 one-off in-app purchases. Function Fitter asks for nothing beyond the download.

Function Fitter ships an update monthly, QuantumPass every 10 months. The most recent releases landed on October 11, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | Function Fitter | QuantumPass |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Monthly** | Every 10 months |
| Size | 4 MB | 3 MB |
| Requires iOS | **17.0** | 17.6 |
| Devices | iPhone, iPad | **iPhone, iPad, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [29Apps LLC](https://appshunter.io/developer/1817021563) | [Valerie Otero](https://appshunter.io/developer/1848585337) |

## What reviewers say

### Function Fitter

[App page](https://appshunter.io/ios/app/function-fitter/id6748284369)

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

**In-app purchases:** none


### QuantumPass

[App page](https://appshunter.io/ios/app/quantumpass/id6755789663)

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Small coffee | $1.99 | one-time |
| Medium coffee | $3.99 | one-time |
| Large coffee | $5.99 | one-time |


## Frequently asked questions

### Is Function Fitter free?

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

### Is QuantumPass free?

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

### Do Function Fitter or QuantumPass have ads?

Neither Function Fitter nor QuantumPass shows ads.

### Which is updated more often, Function Fitter or QuantumPass?

Function Fitter ships an update monthly, and QuantumPass every 10 months. Most recently, Function Fitter was updated on October 11, 2026 and QuantumPass on October 6, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*