PoPoPics.com is aimed to be the largest collection of HD wallpapers, with first ever facility of CROP AND DOWNLOAD.
Hmmmm, you can select the image and crop according to your device's resolution. This allows you to manually select the part of image to download.
Additionally you can download it in mobile by scanning QR Code or entering the short URL in browser ( No app required you see ! ). Cropped image will be downloaded automatically in Phone. ( Obviously internet connection is required in Mobile :P ).
Many other functionality like Celebrity info with official social profiles, Set wallpapers as Facebook Cover, Facebook Photo Comments, SafeSearch, HD Slideshow etc.