Apple iPhone/iPhone 3G (User manual) - Manual (Page 77)

Chapter 7 More Applications 77
See “What You Need” on page 5.
Viewing Photos
Photos synced from your computer can be viewed in Photos. You can also view the roll
of pictures you’ve taken with the built-in camera.
View photos:
1 In Photos:
Tap Photo Library to see all your photos. 
Tap any photo album, or tap Camera Roll to see pictures you’ve taken with iPhone. 
2 Tap a thumbnail to see the photo at full screen.
Show or hide the controls: Tap the full screen photo to show the controls. Tap again
to hide them.
View a photo in landscape orientation: Rotate iPhone sideways. The photo reorients
automatically and, if it’s in landscape format, expands to fit the screen.