Contact
Email support@kestrelwords.com.
For a sign-in problem or a missing subscription, describe what you expected to happen.
Course
For a word, a sentence, or a lesson, email content@kestrelwords.com. That address is on those pages in the app too.
Account
If you sign in with Apple, your progress belongs to that account, and signing in on another phone restores it. Until you sign in, progress stays on your device.
If you are signed in, delete the account in the app. Your progress is deleted with it. An email cannot be matched to an account, because Sign in with Apple does not give us your address, so deletion has to be done from the app while you are signed in. If you are not signed in, deleting the app deletes the progress on your device.
Subscription
If you have a subscription, Apple bills it. To change or cancel it, open Settings, tap your name, then Subscriptions. Request a refund from Apple.
Anything else
Email hello@kestrelwords.com.
The privacy notice explains what an account stores.