How to Save Pictures from Safari on your iPad, iPhone or iPod Touch
Have you ever wanted to permanently save an image while browsing the web with mobile Safari on iOS? It's easy to do! Just touch and hold on the photo for about a second and a menu will pop up with the option to save or copy the picture.
The saved images are automatically placed in the default Photos app under an album called "Saved Photos" or "Camera Roll" depending on your device and version of iOS. From the Photos app you can email a saved picture, assign it to a contact, or use it as your iPod's wallpaper.
Try the touch and hold gesture on photos in other iOS apps and browsers. It works in may apps besides mobile Safari.