Photo Stream is a feature available to iCloud users: It automatically syncs images you take across all your devices. That means the picture you took on your iPhone at the beach will automatically be viewable on your iPad, no cords or syncing required. On iOS devices, Photo Stream will save either your 1000 most recent pictures or the last 30 days' worth of images, whichever is greatest. All you have to do is enable Photo Stream on all your devices. The best part? It doesn't even use your iCloud storage!
Full story from the iMore Blog...