In a year you need to subscribe to the 14.99€/month tier to remove all ads, the 9.99€ tier will show you "a low number of highly relevant ads to provide you with information on how to more optimally use our^Wyour device and support our continued development of these industry leading services".
On a less snarky note, I hate how this has become so common that for some reason this is not "sue the company into non-existence" behavior, but we just sigh and either add the company to our shit list or pay the price because we are now locked in.