Add Stan Sport Subscription through iTunes

Hello Equalibrian,

Is this an app available through the App Store? If not, you will have to continue the subscription from the manufacturer website, or paired with whatever was purchased or it was signed up with.

If it is available through the App Store, signing up through the app purchases with your Apple ID should add the subscription through your Apple ID. You may need to contact the app manufacturer for help with your account: How to contact an app developer - Apple Support

Thanks.