I got it to like 3 months ago, wel whenever it launched.
and yes it has online play,
you and 1 other person swim, and you can write things to each other in the water with pens.
pretty boring game, but great at the same time. not like any normal game youll ever play,
but for me its life ran out after 12 hours play, though if you love it enogh, it could last you around 40-50 hours to find all secrets and fish