Every day there's a new course of six challenges for the paper plane on this page, the same for everyone. Toss it, loop it, fly it through hoops, land it on the X. One clock runs for the whole course, and each challenge earns a medal.
Then dare a friend: the link you share puts your time on that course for them to beat. Your streak and your last week of results stay in your browser. It's free, with nothing to install, and the Paper Plane extension has it a click away on your toolbar.