So Balance: Meditation is an app similar to Headspace / Calm / 10% Happier. They are giving away a free-year long trial atm, then $48.99/yr afterwards but you can cancel early. Just use the app, create an account, go through the first time setup and select one of the locked option (I selected a different plan) and you will be presented with the IAP option.

I can confirm that by just subscribing to the free trial and cancelling right afterwards (in Settings -> iCloud Account -> Subscriptions) will ensure the subscription still active yet you don't have to worry about forgetting to cancel it next year.

Enjoy.