In the past two days, I've come across two types of hacks. The first was the blue turtle, where a guy was just bombarding people with blue turtles, before the prize boxes were even reached! It was an obvious cheat.
Today I came across a new type of hack. I would finish either 1st or 2nd (like clearly finish first or second, no one else around me) and on the scores, I came up 2nd or 3rd behind a guy named Karlos. It was frustrating, especially since I don't get 1st often, and there were two times I clearly finished in first.