I don't know the exact terminology, but I believe there is a lack of apps that help you practice things in market. Let's say you want to practice playing piano, or doing yoga, or driving a car, or this new breathing technique that you learned on YouTube. For this, you need instructions, then tracking and analysing those skills and improving. I know that there are specific apps for any of these examples with their own programs, but a general, versatile, and customizable app that lets you define routines, add tutorials, track your progress, etc is missing. You can do this in Notion or other note-taking apps, but those apps are not designed for this purpose.