You can register through the App Store, where you also manage your subscription billing. For details and billing information about the subscription, check the manage subscription section. (Google Play or Apple Subscriptions) Subscription billing management is not available in the app.

Download The Fitness App

Android - Google Play App Store

https://play.google.com/store/apps/details?id=com.emdigital.jillianmichaels&hl=en_US 

iOS - Apple App Store

https://itunes.apple.com/us/app/my-fitness-by-jillian-michaels/id1190148494