# Engine vs Klyo

The clearest difference is update cadence: Klyo at every 3 days against Engine's every 10 days. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Engine sells 2 in-app purchases, starting at $9.99 per month and Klyo sells 2 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

Engine ships an update every 10 days, Klyo every 3 days. The most recent releases landed on October 28, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Engine | Klyo |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.0 (2 ratings)](https://appshunter.io/ios/app/klyo-weight-gain-tracker/id6770773210/reviews)** |
| Number of ratings | — | **2** |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 10 days | **Every 3 days** |
| Monetization | — | Free with in-app purchases |
| Size | 54 MB | 59 MB |
| Requires iOS | 15.1 | 15.1 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 12+ |
| Developer | [Les Nants](https://appshunter.io/developer/1807100390) | [Bar Cayouf](https://appshunter.io/developer/1896763131) |

## What reviewers say

### Engine

[App page](https://appshunter.io/ios/app/engine-boost-your-vo2max/id6756730497)

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Plan | $9.99 | per month |
| Yearly Plan | $39.99 | per year |


### Klyo

[App page](https://appshunter.io/ios/app/klyo-weight-gain-tracker/id6770773210)

This app helps individuals who struggle to gain weight by tracking their calorie intake. It's designed for 'hard gainers' and busy people who need to increase their food consumption to build muscle.

**Highlights:** Calorie tracking for bulking, Designed for hard gainers, Helps build muscle, Supports busy individuals, Tracks food intake

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Klyo Pro · Monthly | $9.99 | per month |
| Klyo Pro · Yearly | $59.99 | per year |


## Frequently asked questions

### Is Engine free?

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

### Is Klyo free?

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

### Do Engine or Klyo have ads?

Both Engine and Klyo show ads.

### Which is updated more often, Engine or Klyo?

Engine ships an update every 10 days, and Klyo every 3 days. Most recently, Engine was updated on October 28, 2026 and Klyo on October 31, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*