The 500px community is very famous among photography enthusiasts. Along with Flickr, it might be one of the most sought after sites for sharing beautiful and breathtaking pics taken around the globe by amateur and professional photographers alike. It's no surprise then that the service is an excellent fit for the Chromecast and that it wants a place on your TV screen.
500px has worked with Google to bring a curated collection of featured photos from the service to the streaming stick as backdrops. This joins the newly added Facebook and Flickr Albums as an option for photos to display while your Chromecast is idling in the background of your room or office. The Chromecast app will also display the photo's details including the user who took it, its title, and a link to view it on the website.
Hopefully this collaboration will push 500px to update its Android app, which despite supporting Android Wear, still doesn't seem to be able to cast photos to your television.