I've been hearing about this in ads on the dynasty fantasy football podcast I listen to. The way I understand it, it's just a different take on dynasty fantasy sports. In dynasty fantasy sports, you "invest" in players by drafting or trading for them, so I think that's the premise behind it. However, in dynasty fantasy sports, those players eventually score points for your team towards winning a championship and money. In this app, the value is determined kind of similarly, but there's no return other than when you sell your shares. I haven't tried it, it sounds odd to me. But some people apparently enjoy it.