The 24 Hour Wallpaper app is available to purchase on the Mac App Store. From this same page, you can also purchase a complete bundle or individual wallpapers. These include images from Los Angeles, Monument Valley, and Earth from the International Space Station. To first experience 24 Hour Wallpaper, consider downloading the three freebie wallpapers available online. The former lets you bypass Apple's built-in time engine, which some find is both flawed and inflexible. Created by Jetson Creative, 24 Hour Wallpaper is both an app and a stand-alone dynamic desktop bundle.