Apple bills every paid Soco subscription, so you cancel it in your iPhone's settings:

Apple's subscription screen then shows Soco as expiring on a date instead of renewing. That means it's cancelled. If there's no Cancel Subscription button, or Apple shows an expiry date in red, your subscription is already cancelled.

Apple's own guide covers cancelling on an iPad, a Mac or the web, and what to do if Soco isn't in your list: Cancel a subscription from Apple. The confirmation is the same: Soco shows as expiring on a date instead of renewing.

In the Soco app, tap the account icon in the top right, then Manage subscription under Help. If that screen shows your Pro "Via Support", it also shows the date it expires "without further charges". Still check your iPhone's Settings under Subscriptions: if Soco shows there as renewing, Apple is billing you, so cancel it there with the steps above.

After you cancel your Soco subscription you keep Pro until the end of the period you've already paid for. You aren't charged again as long as you cancel at least 24 hours before your renewal date. Apple's own terms say you are charged no more than 24 hours before the next period starts, so a cancellation inside that last day can land after the payment has gone through: Apple Media Services Terms and Conditions, under Subscriptions. Deleting the Soco app or deleting your Soco account does not cancel the subscription; only cancelling in your Apple subscription settings does.

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