If you joined the free trial via the Fiit website, please contact [email protected] and we'll cancel your free trial for you.
If you subscribed via the App Store, you must cancel membership your Apple Subscriptions on your iPhone or iPad:
Launch the Settings app
Tap iTunes and App Store
Tap on your Apple ID
Tap View Apple ID when the popup window appears
Enter your Apple ID password or fingerprint ID when prompted
Tap subscriptions
Tap Fiit to cancel your membership
The subscription should now read 'expires' on your renewal date