Because this is "hacker"news and people here like to reverse engineer things! Also, great work with the game. It's really fun and quite an interesting mind game once it starts getting faster and faster. I agree with the mobile app sentiment... it would be a fun game to play on a commute. Great job!

You could create a backend service that generates 1px swatches of a color; of course, this will only make it one step more difficult to cheat.