# Fast vs CaffeineX

The clearest difference is update cadence: CaffeineX at every 3 days against Fast's every 2 weeks. CaffeineX also leads on iOS requirement (17.0 vs 26.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Fast ships an update every 2 weeks, CaffeineX every 3 days. The most recent releases landed on September 30, 2026 and October 7, 2026 respectively.

## The numbers

| Metric | Fast | CaffeineX |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 weeks | **Every 3 days** |
| Size | 35 MB | 3 MB |
| Requires iOS | 26.0 | **17.0** |
| Devices | **iPhone, iPad, Apple Watch** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [CodeHive](https://appshunter.io/developer/1196672412) | [来 徐](https://appshunter.io/developer/1871065941) |

## What reviewers say

### Fast

[App page](https://appshunter.io/ios/app/fast-intermittent-fasting/id6741595659)

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


### CaffeineX

[App page](https://appshunter.io/ios/app/caffeinex/id6760469305)

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

**In-app purchases:** none


## Frequently asked questions

### Is Fast free?

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

### Is CaffeineX free?

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

### Do Fast or CaffeineX have ads?

Neither Fast nor CaffeineX shows ads.

### Which is updated more often, Fast or CaffeineX?

Fast ships an update every 2 weeks, and CaffeineX every 3 days. Most recently, Fast was updated on September 30, 2026 and CaffeineX on October 7, 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.*