Knuckly privacy policy
Last updated: 28 September 2026
Who we are. Knuckly is made by Kronyx Labs, an independent app developer in the Netherlands. Contact: support@knuckly.app.
The short version
Knuckly keeps your data on your phone. There is no account, no server, no analytics, no advertising and no tracking. We (the developer) never receive your data.
What Knuckly stores, and where
Only on your phone, in the app's private storage:
- training sessions, weekly plans, round-timer progress, lessons read;
- if you add them: weight, height, birth year, sex, food log, goals, fight details and notes, daily check-ins;
- settings (appearance, timer cues, mirror mode, macro split, and a device-local confirmation that your eighteenth birthday has passed when needed).
Some of this is health-related information. It never leaves your phone unless you create and share a backup file.
What is sent over the internet
- Packaged-food search and barcode scan only: the words you type or the barcode number go to Open Food Facts (openfoodfacts.org), a public database run by a French non-profit. Like any website, they receive your IP address. Their privacy policy applies to that request. Nothing about you, your food log or your weight is sent.
- Lesson sources: tapping a source opens its website in your browser. The site receives ordinary browser request information, including your IP address; Knuckly does not attach training, food or weight records.
- Basic foods (USDA, Ciqual), lessons and voice clips are bundled and work offline.
Health Connect (Android, optional)
If you turn it on, you choose whether Knuckly may read your recent workouts, steps and heart rate from Health Connect on your phone. Knuckly reads them only when you ask, never in the background, never uploads them and never writes to Health Connect. Records you preview stay in memory; workouts you choose to save become part of your training log and of any backup file you create. Turning off access stops future reads; saved workouts can be deleted from the log.
Reminders
Training reminders are optional notifications scheduled on your phone. Knuckly asks for notification permission only when you turn them on. No push service is used. Resetting the app or restoring a backup cancels them.
Camera
Used only by the barcode scanner and mirror mode (shadowboxing), and asked for only there. The camera image is shown live and is never recorded, saved or sent.
Microphone, location, contacts
Not used and not requested.
Backups
Android's automatic cloud backup is turned off for Knuckly. If you create a backup file, it is saved where you choose and is not encrypted: anyone with the file can read it. Favourite foods, saved meals, water entries and food preferences stay on the phone and are not included in backup files.
This website
knuckly.app is served by Cloudflare. It uses no cookies, analytics or trackers. Like any web host, Cloudflare processes your IP address and basic request details to deliver the pages and protect the site against attacks.
If you email support@knuckly.app, we use your address and message only to reply to you.
Your rights and deleting data
Because your data stays on your phone, you are in full control: Profile → Reset app erases it, and uninstalling Knuckly deletes it too. We hold no copy, so there is nothing for us to access, correct or delete. For questions, contact support@knuckly.app. You can also complain to a data protection authority; in the Netherlands that is the Autoriteit Persoonsgegevens.
Children
Knuckly is for people aged 16 and over. Make-weight plans are limited to adults (18+).
Changes
If this policy changes, we update it here and the app asks you to agree again before you continue.