The most recent update (April 16th, 2015) to Streetpass added two new games, the Game Vault, and other upgrades. However, I don't recall anything in the Nintendo Direct video nor in any articles about the gold stars I now see on some of my games. In the picture, you can see that Find Mii I & II, Mii Force, and Flower Town all have gold stars next to them.
I so far haven't been able to find anything online about them. At first I thought it might be for finishing a game but I haven't finished Flower Town by far. I have finished the main campaigns of the other two games, but Mii Force isn't perfected.
What do the the gold medals on these games mean?