# KY vs S55

The clearest difference is in-app purchases: S55 at none against KY's 2. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. KY sells 2 in-app purchases, starting at $18.99 per month. S55 asks for nothing beyond the download.

Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on November 3, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | KY | S55 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (8 ratings)](https://appshunter.io/ios/app/ky-fitlive/id1552689108/reviews)** | — |
| Number of ratings | **8** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 months | Every 3 months |
| Monetization | Free with in-app purchases | — |
| Size | 101 MB | 16 MB |
| Requires iOS | 16.6 | **15.0** |
| Devices | **iPhone, iPad, Apple TV** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [KY-FIT SPORT AND FITNESS S.L.](https://appshunter.io/developer/1552689110) | [Trainin B.V.](https://appshunter.io/developer/1732652497) |

## What reviewers say

### KY

[App page](https://appshunter.io/ios/app/ky-fitlive/id1552689108)

Access live and on-demand guided workouts, personalized training, and nutrition plans. Learn proper technique with video demonstrations and enjoy extra classes for flexibility and mobility, all designed to fit your fitness goals and schedule.

**Highlights:** Live guided workouts, Personalized training plans, Nutrition plans, Technique video tutorials, On-demand extra classes, Mobility and stretching sessions

**Features:** Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| KY-FIT.LIVE Monthly | $18.99 | per month |
| KY-FIT.LIVE Yearly | $185.99 | per year |


### S55

[App page](https://appshunter.io/ios/app/s55/id6761461295)

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

**In-app purchases:** none


## Frequently asked questions

### Is KY free?

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

### Is S55 free?

S55 is free to download, with no in-app purchases.

### Do KY or S55 have ads?

Neither KY nor S55 shows ads.

### Which is updated more often, KY or S55?

KY ships an update every 3 months, and S55 every 3 months. Most recently, KY was updated on November 3, 2026 and S55 on October 14, 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.*