Tap or click and the bird rises; do nothing and it falls. Gaps in the pipes come at a fixed rhythm and the only skill is deciding, several times a second, whether you are above or below where you should be. Your first run lasts about four seconds.
It is a faithful rebuild of the game that briefly ate 2014, sprites and sound included, and the reason it is worth keeping is that the difficulty curve was never the point. The point is that the failure is instantaneous and the restart is one click, so there is never a moment where stopping feels natural. Ten minutes, unless it is not.