# Blue Box vs Audio Function Generator

The clearest difference is price: Audio Function Generator at Free against Blue Box's $4.99. Audio Function Generator also leads on ratings volume (2.2K vs 3) and update cadence (every 6 weeks vs every 7 months). Blue Box's advantage is in-app purchases (none vs 1) and rating (5.0 vs 4.7). On ads, device support and iOS requirement there is nothing between them.

Audio Function Generator is free to download; Blue Box costs $4.99 up front. Audio Function Generator sells 1 one-off in-app purchase. Blue Box asks for nothing beyond the download.

Blue Box holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Audio Function Generator has 2.2K ratings behind it against 3, so its average is the more settled of the two. Written reviews complicate that: 56% of Blue Box's written reviews are positive against 77% of Audio Function Generator's, so the app with the better star average is not the one people write more warmly about.

Blue Box ships an update every 7 months, Audio Function Generator every 6 weeks. The most recent releases landed on September 11, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | Blue Box | Audio Function Generator |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | **[5.0 (3 ratings)](https://appshunter.io/ios/app/blue-box/id391832739/reviews)** | [4.7 (2.2K ratings)](https://appshunter.io/ios/app/audio-function-generator/id768229610/reviews) |
| Number of ratings | 3 | **2.2K** |
| Positive reviews | 55.6% of reviews | **77.1% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 6 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Best chart rank | **#192** | — |
| Size | 2 MB | 14 MB |
| Requires iOS | **15.0** | 15.5 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Sunshine Valley Systems](https://appshunter.io/developer/327149814) | [Thomas Gruber](https://appshunter.io/developer/342699861) |

## What reviewers say

### Blue Box

[App page](https://appshunter.io/ios/app/blue-box/id391832739)

**Currently charting:** #192 Top Paid · Utilities (US App Store)

Encode and decode DTMF signals using your device's microphone or keypad. Play back tone sequences with adjustable settings, and save them for easy recall. Explore various tone systems, including trunk control and coin signals, for educational and utility purposes.

**Highlights:** Encode/decode DTMF signals, Adjustable tone, delay, and volume, US, UK, and European tone systems, Multi-frequency and trunk control tones, Coin tone sequences (Red Box mode), Custom tone creation, Save and organize sequences

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

**In-app purchases:** none


### Audio Function Generator

[App page](https://appshunter.io/ios/app/audio-function-generator/id768229610)

Generate various audio test tones, including sine, square, triangle, and sawtooth waves. Explore frequency and volume sweeps, noise generation, and custom preset creation. Advanced features like extended frequency ranges and multi-tone playback are available with an upgrade.

**Highlights:** Generate sine, square, triangle, and sawtooth tones, Frequency and volume sweep generation, Noise generation (white, pink, violet, etc.), Custom preset creation and saving, Extended frequency range (PRO feature), Multi-tone playback (PRO feature)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Upgrade to PRO | $9.99 | one-time |

**What reviewers like**

- 👍 Great app
- 🎶 Helps with Tinnitus
- 💯 Best app I've paid for
- 🔍 Highly recommended
- 🎨 Attention to detail

**What reviewers complain about**

- 🐛 Crashes
- 💰 Deceptive/Money hungry
- 🔒 Basic features paywalled
- 🔒 Limited without paying
- 🔒 Removed functionality to push paid version

**Reported bugs**

- Crashes on launch
- Volume slider issues
- Airplay not working
- Sound distortion when display is active

**Requested features**

- Add download/save feature for custom sounds
- Improve sweep function (continuous mode, better frequency control)
- Add more multi-frequency rows
- Implement 432Hz base frequency option
- Add phase control for noise generators


## Frequently asked questions

### Is Blue Box free?

Blue Box costs $4.99, with no in-app purchases.

### Is Audio Function Generator free?

Audio Function Generator is free to download, with in-app purchases available.

### Which has better reviews, Blue Box or Audio Function Generator?

Blue Box is rated higher. Blue Box averages 5.0 out of 5 from 3 ratings, while Audio Function Generator averages 4.7 from 2.2K ratings.

### Do Blue Box or Audio Function Generator have ads?

Neither Blue Box nor Audio Function Generator shows ads.

### Which is updated more often, Blue Box or Audio Function Generator?

Blue Box ships an update every 7 months, and Audio Function Generator every 6 weeks. Most recently, Blue Box was updated on September 11, 2026 and Audio Function Generator on September 24, 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.*