A. Getting started
- Choose your intended fast length in hours (or days and hours), press Start, and you’re fasting.
- Once the fast is running:
- The progress bar tracks your fast against your intended hours. Its colour shifts from grey to yellow to green as you progress — each colour tied to the metabolic state your body is entering.
- A status message below the bar briefly describes what’s happening in your body at that stage.
- A summary line shows the percentage of intended time elapsed and the projected completion time.
- Dry fasting: if you plan to go without any liquids for longer than 12 hours — even as part of a longer water fast — enable Dry Fast in Settings and flip the toggle when you begin. You can adjust the dry-to-water fast multiplier or leave it at the default of 3 (meaning 1 day of dry fasting is treated as equivalent to 3 days of water fasting). The app recalculates your effective fast hours accordingly.
- Fast-mimicking mode: if you eat something during a fast — intentionally or by accident — but your intake stays under 500 kcal in any 24-hour window, toggle on Fast-Mimicking mode instead of ending the fast. This doesn’t change your effective fast hours; it adds a visual marker to the progress bar so you can see when you were in a fast-mimicking window.
How dry fasting shows on the progress bar: dry fast time appears as a black dotted line for the first 12 hours. If you stop the dry fast before 12 hours, the dotted line stays as a visual marker but doesn’t affect your effective hours. Once you pass 12 hours, the line turns solid and the app multiplies those hours by your multiplier to calculate effective fast time. Example: 16 hours of dry fasting × 3 (default multiplier) = 48 effective fast hours.
B. Notes and mood log
During a fast, you can log your mood on a 1–10 scale. Press Save and the rating appears directly on the progress bar, giving you a visual map of how you felt over the course of the fast.
You can also add timestamped notes at any point. These become valuable when you review past fasts — patterns emerge, and you learn what works for your body. Notes and photos are included when you export your data, making them especially useful if you run your fasting history through an AI tool for analysis.
The free version includes mood logs and text notes. Premium adds photo attachments — snap a photo or pick one from your library.
C. Data export
Your data stays on your device — the app doesn’t store anything externally. Whenever you want, go to Settings → Export Data and everything is saved as a .json file.
JSON is readable by a wide range of apps and is ideal for AI analysis, either on its own or combined with data from smart scales, rings, or watches.