If you're a fan of space exploration and NASA, check out the NASA Image of the Day lockscreen wallpaper app for Windows Phone 8.
NASA Image of the Day will rotate your Windows Phone 8 lockscreen wallpaper daily with a different photo from the NASA library. Everything from launch day photos to photos of the cosmos. Toast notifications are in place to alert you when the image changes.
Images can be saved to your phone and a small description is available from within the app itself on each photo. You can share the images from within the app by email, text, and your social websites. The only downside to the app is that you can view previously used wallpapers without saving them to your Windows Phone.
NASA Image of the Day is an free, ad-supported app for your Windows Phone 8 device and you can find it here at the Windows Phone Store.
Thanks, Gabriel, for the tip!