Follow these simple rules to extend your battery life:

Everything else you need to know is in Chapter 1.

If the iPod or iPhone display has excessive moisture on it from humidity or wet fingers, wipe it with a soft, dry cloth. If it's dirty, use a soft, slightly damp, lint-free cloth — an inexpensive eyeglass cleaning cloth sold in vision-care stores or pharmacies is a good choice. By no means should you use window cleaners, household cleaners, aerosol sprays, solvents, alcohol, ammonia, or abrasives — they can scratch or otherwise damage the display. Also, try not to get any moisture in any of the openings, as it could short out the device.

Use your iPod touch, iPhone, or iPod nano as a workout companion with Nike+ running shoes and a Nike + iPod Sport Kit. The kit's sensor fits inside your Nike+ shoe under the insole. A receiver is provided for the iPod nano and first-generation iPod touch (current-generation iPod touch and iPhone models include a receiver).

When you have the kit and the shoes, activate the app on your iPod touch or iPhone — choose Settings

You can track your pace, time, and distance from one workout to the next, and you can pick songs and playlists to match. You can even sync your workout data with Nikeplus.com, see all your runs, and share motivation with runners across the world.

Ratings are useful — the Shuffle and Genius features are influenced by ratings, and you can define smart playlists with ratings to select only rated songs so that you can avoid the clunkers and spinal tappers. In fact, when you try to put a music library on your iPod or iPhone that's larger than the device's capacity, iTunes decides which songs to synchronize based on — you guessed it — ratings.

iTunes lets you rate your songs, but so does your iPod or iPhone. You can rate any song on your iPod or iPhone as you listen to it. Ratings you assign on your iPod or iPhone are automatically resynchronized to your iTunes library when you connect your iPod or iPhone again.

To assign a rating to a song, start playing the song on your iPod or iPhone (see Chapter 16 for details). The Now Playing screen should appear. On an iPod nano or iPod classic, press the Select button three times, cycling through the scrubber bar and Genius Start button to reach the rating bullets; then scroll the click wheel to give the song zero to five stars.

On an iPod touch or iPhone, follow these steps to rate your songs:

The upper limit is five stars (for the best).

You can turn off the synchronization of certain apps in your iTunes library before syncing your iPod touch or iPhone to iTunes, as I describe in Chapter 9, so that the apps disappear from your iPod touch or iPhone. But you can also delete apps directly from your iPod touch or iPhone.

Touch and hold any icon on the Home screen until all the icons begin to wiggle (as if you're about to rearrange them or add Home screens). To delete an app, tap the circled x that appears inside the app's icon as it wiggles. The iPod touch or iPhone displays a warning that deleting the app also deletes all its data; tap Delete to go ahead and delete the app and its data, or tap Cancel to cancel.

To stop the icons from wiggling, press the physical Home button on the device, which saves any changes you made to your Home screens.

Need more room on your iPod touch or iPhone? You can delete a video or podcast episode directly from your iPod touch or iPhone by flicking left or right across the video or podcast episode selection and then tapping the Delete button that appears.

Your video or podcast episode is deleted from your iPod touch or iPhone only. When you sync your iPod touch or iPhone with iTunes, the video or podcast episode is copied back to your iPod touch or iPhone unless you change your sync settings or switch to manually managing music and videos, as I describe in Chapter 9. Note: If you delete a rented movie from an iPod touch or iPhone, it's gone forever (or until you rent it again).

The Maps app supplied with the iPhone and iPod touch not only shows you the route to take, but in some areas, it can also show you traffic patterns so that you can avoid the jams. The traffic data is constantly updated and aggregated from a variety of Internet sources by Google. It is available for more than 30 major U.S. cities, including New York, Los Angeles, San Francisco, and Washington.

To use Maps, tap Maps on the Home screen. The Maps app appears (refer to Chapter 21). You can obtain directions first, as I describe in Chapter 21, or just display any location on the map that has highways. To show traffic information, tap the Underneath button (the curled-page icon in the lower-right corner) to see a menu underneath the map and then tap Show Traffic.

When the map shows traffic, highways are color-coded according to the flow of traffic:

If you don't see color-coded highways, you may need to zoom out to see highways and major roads.

To stop showing the traffic, tap the Underneath button and then tap Hide Traffic.

You can turn on keyboards for different languages and use them simultaneously. To turn on international keyboards, choose Settings

Figure 23-1. Turn on international keyboards (left), switch languages on the keyboard (middle), and draw Chinese characters (right).

You can turn on any of the keyboards you need — tap Off to turn each one on. To access languages with more than one keyboard, such as Japanese, tap Japanese first and then tap the specific keyboard layout (QWERTY or Kana).

You can then switch keyboards while typing information by tapping the globe icon, as shown in Figure 23-1 (middle), that appears to the right of the 123 key when more than one international keyboard is turned on. The language of the newly active keyboard appears briefly on the spacebar.

Each time you tap the globe icon, the keyboard layout switches to the next language you've turned on, in the order that they appear in the international keyboards list.

To use the Japanese Kana keyboard, use the keypad to select syllables. For more syllable options, tap the arrow key and select another syllable or word from the window. With the Japanese QWERTY keyboard, you can use the QWERTY layout to input code for Japanese syllables. As you type, suggested syllables appear, and you can tap the syllable to choose it.

The iPod touch and iPhone offer keyboards for both Traditional and Simplified Chinese, with Handwriting and Pinyin layouts for both. Turn on international keyboards as described in the preceding section and tap Chinese (Simplified) or Chinese (Traditional). Then tap Off to turn on Handwriting or Pinyin. (You can turn both on.)

For the Handwriting layouts, use the touchpad to enter Chinese characters with your finger. (Refer to Figure 23-1, right side.)

As you draw character strokes, matching characters appear in a list, with the closest match at the top. When you choose a character, its related characters appear in the list as additional choices.

For Simplified Pinyin, use the QWERTY keyboard to enter Pinyin for Chinese characters; as you type, suggested Chinese characters appear. Tap a character to choose it or continue entering Pinyin to see more character options.

Your iPod touch or iPhone remembers your Wi-Fi connections and automatically uses one when it detects it within your range. If you've used multiple Wi-Fi networks in the same location, it picks the last one you used. (For details on choosing a Wi-Fi network, see Chapter 4.)

But if your iPod touch or iPhone keeps picking up a Wi-Fi network that you can't properly join, such as a private network that requires a password you don't know or a commercial network that charges for access, you can tell your iPod touch or iPhone to forget this particular network, rather than turning off Wi-Fi itself. This is very useful if a paid service has somehow gotten hold of your iPod touch or iPhone and won't let you move on to other Web pages without typing a password.

Choose Settings