The touch screen is your mouse, keyboard, dialing pad, and note pad. It’s
going to get fingerprinty and streaky, although it wipes clean with a quick rub
on your sleeve. You can also use it as a mirror when the iPhone is off.
geeks may enjoy knowing that the screen is 320 by 480 pixels.
But what about scratches? Fortunately, Apple learned its lesson on this one.
The iPhone screen is made of optical-quality, chemically treated glass—not
polycarbonate plastic like the iPod’s screen. It’s actually very difficult to scratch
glass; try it on a window pane some day.
If you’re nervous about protecting your iPhone, you can always get a carrying
case for it. But in general, the iPhone is far more scratch-resistant than the
iPod. Even many Apple employees carry the iPhone in their pockets without
carrying cases.
Camouflaged behind the black glass above the earpiece, where you can’t see
them except with a bright flashlight, are two sensors. First, there’s an ambient-light
sensor that brightens the display when you’re in sunlight and dims it in darker
places. You can also adjust the brightness manually; see page 246.
Second, there’s a proximity sensor. When something (like your head) is close to the
sensor when you’re using the phone functions, it shuts off the screen illumination
and touch sensitivity. Try it out with your hand. (it works only in the Phone
application.) You save power and avoid tapping buttons with your cheekbone.
