Subscriptions are billed tot he payment method provided when the subscription is activated and are set to automatically renew at the end of each billing period. So yearly. Our Yearly subscriptions are billed as one up-front payment for the full year at the time of subscribing.

If you bought the subscription through our iOS App: you will be charged with the primary payment method you selected on your iTunes account.
If you bought the subscription through our Android App: you will be charged with the primary payment method you selected on your Google Play account.

For information on how to check the status of your current subscription or auto-renewing, read this article.