After I purchased my trial, I could not see an overview of my purchase in the app. Also I could never see (or cancell) via iOS subscriptions. Because of this, after my trial period I got into a monthly subscription. After this monthly charge was payd I could cancell the subscription via the app, but this was offcourse too late for what I wanted to spend. Also once you have the premium subscription and you click on a course inside the app (which all seems to be part of your subscr) you are charged again without clear notice of this or the price.
The content of the app is great! But I lost a lot of money without notice. I would recommend looking up face yoga on you tube instead.