Nik released SnapSeed for OS X a while back. It is really good for people who use it on their mobile devices and do not have anything better on the desktop/laptop systems.
Because I have Aperture on my desktop I decided against SnapSeed for OS X but use it on my iOS devices.
|AT-6 Harvard by jarud|
from Trainer aircraft
|Monarch butterflies winter roost at Pismo Beach by cjf2|
from Safety in Numbers (Nature)