Apple iPhone/iPhone 3G (User manual) - Manual (Page 86)

If you have an iPhone 3G, a blue marker indicates your location when GPS is used
to find your location. Otherwise, a circle is used to show your approximate location.
As you move around, iPhone updates your location, adjusting the map so that the
location indicator remains in the center of the screen. If you tap again or drag the
map, iPhone continues to update your location but stops centering it, so the location
information may move off the screen.
Note: To conserve battery life, turn Location Services off when you’re not using it. In
Settings, choose General > Location Services.
Use the dropped pin: Tap , then tap Drop Pin.
A pin drops down on the map, which you can then drag to any location you choose.
Quickly move the pin to the area currently displayed: Tap , then tap Replace Pin.
86 Chapter 7 More Applications