You can cancel Wakeout at any time. Apple handles billing, so you cancel through Apple. It takes about a minute.
How to cancel
In Wakeout, open Settings and tap "manage subscription". (Or open the App Store, tap your profile picture in the top right, then Subscriptions.)
Tap Wakeout.
Tap Cancel Subscription and confirm.
You keep Wakeout until the end of the period you already paid for. To avoid the next charge, cancel at least 24 hours before your renewal date.
Good to know
If you do not see Wakeout in the list, you may be signed in with a different Apple Account, or your plan may not be a subscription (see the next point).
Lifetime is a one-time purchase and a gift is a one-time year. Neither renews, so there is nothing to cancel.
Deleting your Wakeout account does not cancel your subscription. Cancel with Apple first, then delete, if you want both.
Charged by mistake, or want a refund? See How to request a refund.
More on Apple's side: Apple Support. If you would like to tell us why you are leaving, we read every message. No pressure.