I’m in general in charge of onboarding process for the companies I work for.
Registration or CPL is just a part of onboarding, mastering user engagement and discovery of your app or service is key, knowing that often the more active the user will be in his first experience of your app, the first minutes, pages, days, more chances that user will have to pay for your service later.
A few services now propose something like that.
For example Appcues, Whatfix, Userlane…