If you've been playing games for longer than twenty minutes, odds are pretty good that someone (probably a woman or an elderly relative) has descended from their ivory tower of age and/or ovaries to blithely comment that you're wasting your time.
Arguing the point is useless — both age and ovaries are formidable opponents — so your only recourse is to make the point so blindingly obvious that your asshole relative/girlfriend/random bystander may as well be questioning the fashion sense of children waiting to catch the bus outside of the School For The Blind.
ODE is a simple game. You're given a white screen populated by randomly moving black pixels that you're asked to tap. Tap one and it bursts into a colorful skull. Once you're bored tapping dots, you can upload your total kill tally to the game's servers to see how many people have likewise wasted minutes exploding black dots.
And that's it. That's the whole "game."
I don't yet know if it's an ingenious commentary on simplistic game design or how easily entertained the masses are, but since it's a free iPhone game (App Store link) that I've wasted easily an hour on over the last few days, I'd say there are far worse ways to kill the hours until school/work/your depressing life comes to an end.