# SPL Meter vs AiON

The clearest difference is in-app purchases: AiON at none against SPL Meter's 2. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. SPL Meter sells 2 in-app purchases, starting at $1.99 per 7 days. AiON asks for nothing beyond the download.

SPL Meter ships an update every 5 weeks, AiON every 6 weeks. Both last shipped on September 13, 2026.

## The numbers

| Metric | SPL Meter | AiON |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (9 ratings)](https://appshunter.io/ios/app/spl-meter-dbtracker/id6742470686/reviews)** | — |
| Number of ratings | **9** | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 5 weeks** | Every 6 weeks |
| Monetization | Free with in-app purchases | — |
| Size | 9 MB | 85 MB |
| Requires iOS | **15.0** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [金红 李](https://appshunter.io/developer/1781133144) | [TeLIoT](https://appshunter.io/developer/1315634104) |

## What reviewers say

### SPL Meter

[App page](https://appshunter.io/ios/app/spl-meter-dbtracker/id6742470686)

This tool measures ambient noise levels in real-time, providing decibel readings to help you understand noise intensity and protect your hearing. It features an intuitive gauge, explanations of noise levels, and recording capabilities to track variations across locations and times.

**Highlights:** Real-time decibel measurement, Intuitive gauge display, Noise level explanations, Recording functionality, Track noise variations, Hearing protection guidance

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlimited access | $1.99 | per 7 days |
| Unlimited access | $9.99 | per year |


### AiON

[App page](https://appshunter.io/ios/app/aion/id6749782122)

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

**In-app purchases:** none


## Frequently asked questions

### Is SPL Meter free?

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

### Is AiON free?

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

### Do SPL Meter or AiON have ads?

Neither SPL Meter nor AiON shows ads.

### Which is updated more often, SPL Meter or AiON?

SPL Meter ships an update every 5 weeks, and AiON every 6 weeks. Most recently, SPL Meter was updated on September 13, 2026 and AiON on September 13, 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.*