One: Track Fasts, Hit Goals

4.2
65 reviews
5K+
Downloads
Content rating
Everyone
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About this app

Achieve your health goals with One, the simple and effective intermittent fasting (IF) tracker designed for focus and consistency.

Built for those who value clarity over clutter, One provides the essential tools to manage your fasting schedule without distractions. We believe that a straightforward approach is the most sustainable way to build a healthy habit. No ads, no subscriptions, no complicated settings. Just a reliable tool to support your journey.

Why Choose One?

Focused & Uncluttered Interface
Our clean design helps you concentrate on your fast, not on navigating a complex app. It's the perfect tool for tracking popular schedules like 16:8 or circadian rhythm fasting.

Effortless Control
Start, stop, edit, and view your fasts with just a few intuitive taps. Tracking your progress and history has never been easier.

Truly Free, For Everyone
One is completely free. We promise zero advertisements, no premium paywalls, and no hidden costs. Ever.

Fast & Lightweight
Launches instantly and runs smoothly, respecting your device's battery and resources.

Seamless Wear OS Integration

Take full control of your fast right from your wrist with features designed for convenience and discretion.

Customizable Complications
Add a Complication directly to your favorite watch face for a constant, subtle view of your timer.

Full Wrist Control
Start, stop, and monitor your fasts without ever touching your phone.

Download One today and experience a more focused approach to intermittent fasting.
Updated on
Mar 16, 2026

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
No data shared with third parties
Learn more about how developers declare sharing
This app may collect these data types
App info and performance
Data is encrypted in transit
Data can’t be deleted

Ratings and reviews

4.1
50 reviews
Liara Jane
September 26, 2025
it is as described. a simple fasting tracker. it can be opened to start and end on the samsung watch. however, there's no features for editing. Your options for timing are limited to just a few basic selections. It does not record your data for later review. choose a time option, hit start, it counts time, hit end. that's it. I give it 3 stars for ease of use, not 5 stars, because there are no other features or customization. maybe it's for you.
1 person found this review helpful
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charlies.bot
January 28, 2026
thank you for the feedback! We have added more customizations in the few latest versions. You can change the start time and the end goal now Hope you can give it another shot!
Anon
March 8, 2026
I like how simple this app is but the timer can be strangely inaccurate at times, the fasting goal and the calculator aren't synced. the fasting goal is 20 hours but the end time shows an hour earlier than the center timer that says the fast is only 95 percent done.
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Sidney Carthell
February 12, 2026
Simple. Unfortunately it suffers from lack of options. There really should be a custom time on the app. Also not including 24hours as an option is strange. Does the job. For what it does, you could set a timer in your native clock app. its basically the same thing.
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charlies.bot
March 2, 2026
In the last version of One you can create custom goals from your phone and sync them with your watch!