Can I cancel Premium?

It depends where you bought it.

• Bought on our website: plans are one-time purchases, not recurring subscriptions. Your access stays active until the expiry date and then simply ends. There is nothing to cancel and no automatic renewal.
• Bought through the Apple App Store: the subscription renews automatically and Apple charges it. Turn off automatic renewal in your device App Store settings to stop it.

If you have a billing question, contact Support from inside the app.