pixR---500px-for-Apple-Watch
https://itunes.apple.com/us/app/pixr-watch-picture-viewer/id1038940504?ls=1&mt=8
http://devpost.com/software/pixr-500px-for-apple-watch
pixR is an extension of the 500px right on your wrist. pixR is 500px images viewer and more for your Apple Watch. It not only lets you browse all the available categories of 500px but also see inside details of the pictures and the photographers too. pixR has a very easy and free flowing UI that lets you browse 500px with a breeze on your Apple Watch. Note: that this app requires Apple watchOS2. It is a stand alone app for your Apple watch and requires a working internet connection on the watch, regardless of the fact that your iPhone is in vicinity or not. Powered by 500px.
Just add your 500px API key in constants.h ("CONSUMER_key") you receive after signing up at 500px developer site.
https://500px.com/settings/applications
#iPhone Screenshots