# WaterFast vs Onefast

The clearest difference is update cadence: Onefast at every 2 days against WaterFast's weekly. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. WaterFast sells 3 in-app purchases, starting at $2.99 per month and Onefast sells 2 in-app purchases, starting at $9.99 per year. Whichever you choose, the download price is not the number that matters.

WaterFast ships an update weekly, Onefast every 2 days. The most recent releases landed on November 5, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | WaterFast | Onefast |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/waterfast-if-fasting-timer/id6787013484/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Weekly | **Every 2 days** |
| Monetization | Freemium | — |
| Size | 3 MB | 4 MB |
| Requires iOS | 17.0 | 17.0 |
| Devices | **iPhone, Apple Watch** | iPhone |
| Age rating | +4 | 4+ |
| Developer | [LUIS ORLANDO LAZO GONZALEZ](https://appshunter.io/developer/1896012382) | [Nguyen Dinh Chung](https://appshunter.io/developer/6805296065) |

## What reviewers say

### WaterFast

[App page](https://appshunter.io/ios/app/waterfast-if-fasting-timer/id6787013484)

This app provides a synchronized intermittent fasting timer designed for seamless use across your iPhone and Apple Watch. It offers detailed insights into fasting zones and hydration tracking, with a focus on privacy and a user-friendly experience.

**Highlights:** Synchronized iPhone and Apple Watch timer, Fasting zone insights, Hydration tracking, Multiple fasting plans, Streak calendar, Data export

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| WaterFast PRO Monthly | $2.99 | per month |
| WaterFast PRO Yearly | $9.99 | per year |
| WaterFast PRO Lifetime | $24.99 | one-time |


### Onefast

[App page](https://appshunter.io/ios/app/onefast-fasting-timer/id6810987516)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Onefast Pro (Yearly) | $9.99 | per year |
| Onefast Pro (Lifetime) | $19.99 | one-time |


## Frequently asked questions

### Is WaterFast free?

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

### Is Onefast free?

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

### Do WaterFast or Onefast have ads?

Neither WaterFast nor Onefast shows ads.

### Which is updated more often, WaterFast or Onefast?

WaterFast ships an update weekly, and Onefast every 2 days. Most recently, WaterFast was updated on November 5, 2026 and Onefast on October 31, 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.*