Underhook — Brazilian Jiu-Jitsu brain training.
Questions, bug reports, feedback, or account requests — email us and we'll get back to you:
We usually reply within 1–2 business days.
To request access to, or deletion of, the data tied to your account, email the address above from the account you use in the app. Deleting the account takes three taps inside the app — here is how. See our Privacy Policy for what we store and why, and the Terms of Use for the rest.
Underhook Pro is billed by the store you bought it from, not by us.
Cancelling stops the renewal; Pro stays until the period you paid for ends.