FastWithin

Privacy Policy

Effective October 6, 2026. FastWithin is published by Harris Apps Studio.

FastWithin is built to need as little of your information as possible. This page explains, in plain English, what the FastWithin app and this website do with data. If anything here is unclear, write to hello@fastwithin.com.

The short version

  • There is no account. We do not ask for your name, your email address or any other personal information.
  • Your fasting data stays on your phone. Your fasting history, meals, notes, bedtime and settings are stored on the device.
  • One optional feature sends a photo. The only thing that can leave your phone is a photo you choose to send with Photo I ate, an optional FastWithin Plus feature.
  • No ads and no tracking. The app has no ads and no analytics or tracking SDKs. This website uses no cookies.
  • Adults only. FastWithin is for people 18 and over.

What stays on your phone

FastWithin keeps your fasting history, the meals and notes you type, your goal, your bedtime, your settings and your notification choices on your device. None of it is sent to us, and we cannot see it.

If Android backup is turned on for your phone, your phone's own backup may include FastWithin's data. That backup belongs to your Google account and your phone settings. We do not receive it and we do not control it. If you choose to export your data or share a card of your fast, that file goes only where you send it.

Notifications (zone changes, your goal, the kitchen cutoff, water breaks and the weekly look back) are scheduled on your phone itself. No server is involved. The weekly coach in Plus is worked out on your phone from your own history, and your history is not sent anywhere to make it.

Purchases

FastWithin Plus is bought through Google Play. Google Play processes the payment, and FastWithin never sees your card details. The app checks with Google Play, on your phone, to know whether Plus is active. Google's own privacy policy covers what Google collects when you buy.

Photo I ate (optional, in Plus)

Photo I ate is off until you turn it on and agree to a short explanation in the app. When you use it:

  1. The photo is sent over HTTPS to FastWithin's AI helper, a small service we run on Cloudflare.
  2. The helper passes the photo to Google's Gemini API, which looks at it and names the food (for example, "Grilled chicken salad"). The helper sends that name back to the app.
  3. FastWithin does not store the photo. The app does not save it to your gallery, and the helper does not keep it.
  4. With the photo, the app sends a random install ID: a random code the app makes the first time it runs. It is not your name, your email address or a hardware ID of your device, and it is not linked to your Google account.
  5. To keep daily limits fair, the helper keeps the install ID and a count of how many AI requests that install made that day. These counters are not linked to you as a person. They hold no photos, no food names and no fasting history.

Google's Gemini API processes the photo under Google's terms and may keep it for a limited time. On Google's unpaid tier, Google may use submitted content to improve its products. Cloudflare and Google may process the photo in countries other than your own. So please do not photograph people or private things.

You can use all of FastWithin without this feature. You can always type what you ate instead.

What we do not collect

We do not collect your name, email address, phone number, location, contacts, health records or advertising ID. Because there is no account, we have no profile of you.

Ads and tracking

FastWithin shows no ads. The app has no analytics or tracking SDKs, and it does not use your advertising ID.

This website

This website uses no cookies and no analytics. It does not load anything from other companies: the fonts, images and scripts are all hosted on the site itself. The site is hosted on Cloudflare, which may keep standard server logs (such as your IP address and the pages requested) to keep the service secure and running, under Cloudflare's own privacy policy.

Children

FastWithin is for adults 18 and over. When you first open the app it asks for your birth year, and it does not let anyone under 18 use it. The year you enter is kept only on your phone. We do not knowingly collect information from children. If you believe a child has used Photo I ate, please contact us.

Your choices and deleting your data

Everything FastWithin stores is on your phone, so you are in control. Open Settings and tap Delete all my data to erase every fast, meal, note and setting. Uninstalling the app removes it too. Settings also has Export my data, which saves your history as a file you can keep.

The delete data page has the steps, and explains what the AI helper keeps.

Security

Anything sent to the AI helper travels over HTTPS, which encrypts it in transit. We keep the helper simple on purpose: it has no accounts, no photo storage and no fasting history.

Changes to this policy

If we change this policy, we will change the date at the top. If a change affects what leaves your phone, we will also say so in the app's update notes. This policy matches the Data safety section of our Google Play listing.

Contact

Harris Apps Studio, Texas, United States.
Email: hello@fastwithin.com