Underhook is a Brazilian Jiu-Jitsu training app. This policy explains what
information the app handles, why, and the choices you have. We keep it short
and plain because that is the honest way to write one.
What we handle
Account & sign-in. You start anonymously. If you choose
Sign in with Apple, Apple gives us a private identifier (and your name, only if
you allow it) so your progress can follow you across devices. Authentication is
managed through our backend provider, Supabase.
Training data. Your lesson progress, belt and stripes, XP,
streaks, and per-question performance are stored so we can sync your account and
personalize which questions you see.
Profile. An optional display name, and an optional academy,
country, or city if you enter them.
Photos & camera (optional). If you take a training
check-in photo, it stays on your device and is only used to render your shareable
check-in card — it is never uploaded to our servers. If you add a profile avatar,
that image is stored in our secure storage until you replace it or delete your
account. You can remove either at any time.
Purchases. Subscriptions are processed by Apple. We receive
your subscription status to unlock Pro features. We never receive your payment card
details.
Diagnostics. Minimal technical logs to operate and debug the app.
What we do not do
We do not collect face data or any biometric data. Photos you take or choose
are used only as your check-in card image or profile avatar — they are never
scanned, analyzed, or used for face recognition or any other processing.
We do not sell your personal data.
We do not use third-party advertising SDKs, and we do not show ads.
Who we share with
Only the service providers needed to run the app: our backend/database host
(Supabase) and Apple (for Sign in with Apple and for processing purchases).
Retention & your choices
Your account data is retained while your account is active. You can delete your
account and all associated data directly in the app: Settings → Account →
Delete Account. Deletion permanently removes your profile, training progress, and any
stored avatar from our servers. Deleting the app removes data stored on your device.
You can also request access to, or deletion of, the data in your account by
contacting us at the address below.
Children
Underhook is not directed to children under 13.
Changes
If this policy changes, we will post the update here with a new effective date.