# Building Acoustics Partner vs Function Fitter

The clearest difference is update cadence: Function Fitter at monthly against Building Acoustics Partner's every 4 months. Building Acoustics Partner's advantage is iOS requirement (15.0 vs 17.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Building Acoustics Partner ships an update every 4 months, Function Fitter monthly. The most recent releases landed on October 10, 2026 and September 25, 2026 respectively.

## The numbers

| Metric | Building Acoustics Partner | Function Fitter |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 months | **Monthly** |
| Size | 160 MB | 4 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Hottinger Bruel & Kjaer A/S](https://appshunter.io/developer/622515894) | [29Apps LLC](https://appshunter.io/developer/1817021563) |

## What reviewers say

### Building Acoustics Partner

[App page](https://appshunter.io/ios/app/building-acoustics-partner/id1487977751)

**Features:** macOS Compatibility

**In-app purchases:** none


### Function Fitter

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

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

**In-app purchases:** none


## Frequently asked questions

### Is Building Acoustics Partner free?

Building Acoustics Partner is free to download, with no in-app purchases.

### Is Function Fitter free?

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

### Do Building Acoustics Partner or Function Fitter have ads?

Neither Building Acoustics Partner nor Function Fitter shows ads.

### Which is updated more often, Building Acoustics Partner or Function Fitter?

Building Acoustics Partner ships an update every 4 months, and Function Fitter monthly. Most recently, Building Acoustics Partner was updated on October 10, 2026 and Function Fitter on September 25, 2026.

---

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