This unlocks five hidden aspirations in the Sims 4.
Four of them are the Tutorial Aspirations - Trend Setter, Chef, Painter, and Athlete. For some of these you need a roommate, so be sure to have one or get one when it comes up. I have to admit, I never played with the tutorial when it was available and never noticed when it went away. But it did go away, it seems, replaced by Emily's popups making this the best way to unlock these aspirations.
And this mod also restores the old Positivity Challenge. You need to call the "Event Coordinator" from the social interaction on your phone which gets it started. After that the trait is unlocked and you can run through it. No time limit now, though!