# Centerline vs SonoSpec

The clearest difference is price: Centerline at Free against SonoSpec's $9.99. Centerline also leads on update cadence (every 5 days vs every 2 months). SonoSpec's advantage is in-app purchases (none vs 1). On ads, device support and iOS requirement there is nothing between them.

Centerline is free to download; SonoSpec costs $9.99 up front. Centerline sells 1 one-off in-app purchase. SonoSpec asks for nothing beyond the download.

Centerline ships an update every 5 days, SonoSpec every 2 months. The most recent releases landed on November 6, 2026 and November 10, 2026 respectively.

## The numbers

| Metric | Centerline | SonoSpec |
| --- | --- | --- |
| Price | **Free** | $9.99 |
| Rating | **[5.0 (4 ratings)](https://appshunter.io/ios/app/centerline-chromatic-tuner/id6801356258/reviews)** | — |
| Number of ratings | **4** | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 5 days** | Every 2 months |
| Monetization | Free with in-app purchases | — |
| Size | 3 MB | 1 MB |
| Requires iOS | 17.0 | 17.0 |
| Devices | iPhone, Mac | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Endpaper Labs LLC](https://appshunter.io/developer/6793820240) | [Corey Thomas Slick](https://appshunter.io/developer/1818871667) |

## What reviewers say

### Centerline

[App page](https://appshunter.io/ios/app/centerline-chromatic-tuner/id6801356258)

This app offers free chromatic tuning for various instruments, identifying notes, sharps, and flats. It includes a dedicated guitar mode with automatic string detection and optional advanced tuning tools for purchase.

**Highlights:** Free chromatic tuning, Dedicated guitar mode, Automatic string detection, Pitch history tracking, Offline functionality, No ads or accounts

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Centerline Complete | $3.99 | one-time |


### SonoSpec

[App page](https://appshunter.io/ios/app/sonospec-spectrum-analyzer/id6804465268)

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

**In-app purchases:** none


## Frequently asked questions

### Is Centerline free?

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

### Is SonoSpec free?

SonoSpec costs $9.99, with no in-app purchases.

### Do Centerline or SonoSpec have ads?

Neither Centerline nor SonoSpec shows ads.

### Which is updated more often, Centerline or SonoSpec?

Centerline ships an update every 5 days, and SonoSpec every 2 months. Most recently, Centerline was updated on November 6, 2026 and SonoSpec on November 10, 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.*