I think I found the new, or relatively new "Flappy Bird" or "Angry Bird" or "Cookie Clicker" nonsense and it's "Wormax.io". I think the more original version might've been a game called "Slither", but I played Wormax for far too long lol It's a browser and mobile game, you play as a worm who collects glowy things to grow bigger, going up against other people on a server that is always running, trying to stay on top of the leaderboard. You die if you bump into the side of anyone else, so it's a game of you trying to get others to hit your side or get surrounded so you can wipe them out. It's just one of those odd, minimal effort, time wasters, but I dig the casual multiplayer gameplay of this one. It can be incredibly addicting as once you get into the top 10 and you know you are huge and you are trying to manage your size to wrap up folks.
In a way, now that I think about it, it's almost like a free form Pac-Man, but instead of clearing rigidly designed levels, and fighting ghosts, you just grow into a bigger Pac-Man, eating mass amounts of pellets, fighting other growing Pac-Men lol