# Zygo vs SFS App

The clearest difference is in-app purchases: SFS App at none against Zygo's 2. SFS App also leads on device support (3 vs 1) and iOS requirement (13.0 vs 16.6). On price, update cadence and ads there is nothing between them.

Both are free to download. Zygo sells 2 in-app purchases, starting at $4.99 per month. SFS App asks for nothing beyond the download.

Zygo ships an update every 2 months, SFS App every 3 months. The most recent releases landed on October 11, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | Zygo | SFS App |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.3 (123 ratings)](https://appshunter.io/ios/app/zygo/id1564866603/reviews)** | — |
| Number of ratings | **123** | — |
| Positive reviews | 42.9% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 3 months |
| Monetization | Free with in-app purchases | — |
| Size | 100 MB | 24 MB |
| Requires iOS | 16.6 | **13.0** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Swimmersive Co](https://appshunter.io/developer/1381489863) | [DEVBUNCH (PRIVATE) LIMITED](https://appshunter.io/developer/1659598631) |

## What reviewers say

### Zygo

[App page](https://appshunter.io/ios/app/zygo/id1564866603)

Access over 500 guided swim workouts paired with music. Track your progress with lap counting and a tempo trainer. Stay connected with walkie-talkie functionality and manage device settings.

**Highlights:** 500+ guided swim workouts, Music integration, Lap counting, Tempo trainer, Walkie-talkie feature, Battery level monitoring, Firmware updates

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Subscription | $4.99 | per month |
| Yearly Subscription | $49.99 | per year |


### SFS App

[App page](https://appshunter.io/ios/app/sfs-app/id6756957521)

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

**In-app purchases:** none


## Frequently asked questions

### Is Zygo free?

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

### Is SFS App free?

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

### Do Zygo or SFS App have ads?

Neither Zygo nor SFS App shows ads.

### Which is updated more often, Zygo or SFS App?

Zygo ships an update every 2 months, and SFS App every 3 months. Most recently, Zygo was updated on October 11, 2026 and SFS App on October 6, 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.*