I ran into a problem yesterday when my application was rejected. Apparently the images are not being displayed on the actual Apple Watch, however they are being displayed in
As of Xcode 6.3, iOS 8.3:
Leave off the ".png" part of the image name. It will look strange in the storyboard, showing a blue "?", instead of the image thumbnail, but will work on both the simulator and watch. Same goes for specifying PNGs for Context Menus and programmatically specifying animation.