Chapter 1. The Guided Tour
If you’d never seen all the videos and photos of the iPhone, and you found it lying on someone’s desk, you might not guess it was a phone (let alone an iPod/Web browser/alarm clock/stopwatch/voice recorder/musical instrument/compass). You can’t see any antenna, mouthpiece, or earpiece—and, goodness knows, there are no number keys for dialing.
It’s all there, though, hidden inside this sleek black-and-silver slab.
For the rest of this book, and for the rest of your life with the iPhone, you’ll be expected to know what’s meant by, for example, “the Home button” and “the Sleep switch.” A guided tour, therefore, is in order. Keep hands and feet inside the tram at all times.
Sleep Switch (On/Off)
It has several functions:
On/Off. The same switch can also turn the iPhone off completely so it consumes no power at all; incoming calls get dumped into voicemail. You might turn the iPhone off whenever you’re not going to use it for a few days.
To turn the iPhone off, press the Sleep switch for 3 seconds. The screen changes to say slide to power off. Confirm your decision by placing a fingertip on the right-pointing red arrow and sliding to the right. The device shuts off completely.
If you change your mind about turning the iPhone off, tap the Cancel button, or do nothing. If the iPhone decides you’re not paying attention, it dismisses the slide to power off screen automatically.
You can also tap it twice to dump the call to voicemail immediately. (Of course, because they didn’t hear four rings, iPhone veterans will know you’ve blown them off. Bruised egos may result. Welcome to the new world of iPhone etiquette.)
Force restart. The Sleep switch has one more function. If your iPhone is frozen, and no buttons work, and you can’t even turn the thing off, this button is also involved in force-restarting the whole machine. Steps for this last-ditch procedure are on Reset: Six Degrees of Desperation.
When you don’t touch the screen for 1 minute, or when you put the iPhone to sleep, the phone locks itself. When it’s locked, the screen isn’t touch-sensitive. Fortunately, you can still take phone calls and control music playback.
Remember, this phone is all touchscreen, so it’s much more prone to accidental button pushes than most phones. You wouldn’t want to discover that your iPhone has been calling people or taking photos from the depths of your pocket or purse. Nor would you want it to dial a random number from your back pocket, a phenomenon that’s earned the unfortunate name butt-dialing.
That’s why the first thing you do after waking the iPhone is unlocking it. Fortunately, that’s easy (and a lot of fun) to do: Place your fingertip on the gray arrow and slide it to the right, as indicated by the animation.
The iPhone can demand a password each time it wakes up, if you like. See General. On the other hand, you can adjust how quickly the phone locks itself, or make it stop locking itself altogether; see General again.
Sim Card Slot
On the edge of the phone, at the top (iPhone 3G and 3GS) or the right side (iPhone 4), there’s a tiny pinhole next to what looks like a very thin slot cover. If you push an unfolded paper clip straight into the hole, the SIM card tray pops out.
It turns out that there are two major cellphone network types: CDMA, used by Verizon and Sprint, and GSM, used by AT&T, T-Mobile, and most other countries around the world. Your iPhone works only on GSM networks. (One huge reason that Apple chose AT&T as its exclusive carrier is that Apple wanted to design a phone that would work overseas.)
Every GSM phone stores your phone account info—details like your phone number and calling-plan details—on a tiny memory card known as a SIM card (Subscriber Identity Module). On some phones, though not the iPhone, it even stores your address book.
What’s cool is that, by removing the card and putting it into another GSM phone, you transplant the iPhone’s brain. The other phone now knows your number and account details, which can be handy when your iPhone goes in for repair or battery replacement.
(The iPhone 4 uses a smaller type called a MicroSIM, which isn’t compatible with nearly as many other phone models. But give it time.)
Apple thinks SIM cards are geeky and intimidating and that they should be invisible. That’s why, unlike most GSM phones, your iPhone came with the card preinstalled and ready to go. Most people will never have any reason to open this tray, unless they just want to see what a SIM card looks like.
You can’t use any other company’s SIM card in the iPhone—it’s not an “unlocked” GSM phone (at least, not officially; there are some unauthorized ways). Other recent AT&T cards work, but only after you first activate them. Insert the other card—it fits only one way, with the AT&T logo facing up—and then connect the iPhone to your computer and let the iTunes software walk you through the process.
If you were curious enough to open it up, you can close the tray simply by pushing it back into the phone until it clicks.
This little hole is more than an ordinary 3.5-millimeter audio jack, however. It contains a secret fourth pin that conducts sound into the phone from the microphone on the earbuds’ cord. Now you, too, can be one of those executives who walk down the street barking orders, apparently to nobody. The iPhone can stay in your pocket as you walk or drive. You hear the other person through your earbuds, and the mike on the cord picks up your voice.
But one of the best unsung features of the iPhone 3GS and iPhone 4 is the oleophobic screen. That may sound like an irrational fear of yodeling, but it’s actually a coating that repels grease. You’ll be amazed at how easily a single light wipe on your clothes restores the screen to its right-out-of-the-box crystal sheen.
You can also use the screen as a mirror when the iPhone is off.
Geeks may enjoy knowing that the screen is 320 x 480 pixels on the iPhone 3G and 3Gs. But the iPhone 4, whose screen Apple calls the Retina display, packs in an astonishing 640 x 960 pixels. That’s four times as sharp as the previous iPhones, and higher resolution than any phone on the market. It’s really, really sharp, as you’ll discover when you try to read text or make out the details of a map or photo.
But what about scratches? Fortunately, Apple learned its lesson on this one. The iPhone screen (and the iPhone 4’s back panel, too) 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 windowpane someday.
If you’re nervous about protecting your iPhone, you can always get a case for it (or a “bumper” for the iPhone 4—a silicone band that wraps around the metal edges). 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 Brightness.
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.
Cell signal. As on any cellphone, the number of bars indicates the strength of your cell signal, and thus the quality of your call audio and the likelihood of losing the connection. If there are zero bars, then the dreaded words “No service” appear here.
or Network type. The means your iPhone is connected to the Internet via AT&T’s very slow EDGE cellular network. In general, if you have a cell signal, you also have an EDGE signal. (If you see this one , that means GPRS, better known as “the even older, even slower Internet network,” is in operation instead.)
Airplane mode. If you see the airplane instead of signal and WiFi bars, then the iPhone is in Airplane mode (Airplane Mode).
WiFi signal. When you’re connected to a wireless WiFi Internet hot spot (A Tale of Three Networks), this indicator appears. The more “sound waves,” the stronger the signal.
The iPhone is locked—meaning that the screen and most buttons don’t work, to avoid accidental presses—whenever it goes to sleep. See About MissingManuals.com.
9:50 AM. When the iPhone is unlocked, a digital clock replaces the lock symbol. To set the clock, see General.
Play indicator. The iPhone is playing music. Before you respond, “Well, duh!” keep in mind that you may not be able to hear the music playing. For example, maybe the earbuds are plugged into the iPhone but aren’t in your ears. So this icon is actually a handy reminder that you’re running your battery down unnecessarily.
Alarm. You’ve got an alarm set. This reminder, too, can be valuable, especially when you intend to sleep late and don’t want an alarm to go off. See Alarm for setting (and turning off) alarms.
Bluetooth connection. The iPhone is connected wirelessly to a Bluetooth earpiece or a hands-free car system, as described on Car Kits. (If this symbol is gray, then it means that Bluetooth is turned on—and draining your battery—but that it’s not connected to any other gear.)
TTY symbol. You’ve turned on Teletype mode, meaning that the iPhone can communicate with a Teletype machine. (That’s a special machine that lets deaf people make phone calls by typing and reading text. It hooks up to the iPhone with a special cable that Apple sells from its Web site.)
Call forwarding. You’ve told your iPhone to auto-forward any incoming calls to a different phone number (Call Forwarding). This icon is awfully handy—it explains at a glance why your iPhone never seems to get calls anymore./
VPN. You corporate stud, you! You’ve managed to connect to your corporate network over a secure Internet connection, probably with the assistance of some highly paid system administrator—or by consulting A Word on Troubleshooting.
Battery meter. When the iPhone is charging, the lightning bolt appears. Otherwise, the battery logo “empties out” from right to left to indicate how much charge remains. (On the iPhone 3GS and iPhone 4, you can even add a “% full” indicator to this gauge; see Brightness.)
Rotation lock. This icon reminds you that you’ve deliberately turned off the screen-rotation feature, where the screen image turns 90 degrees when you rotate the phone. Why would you want to? And how do you turn the rotation lock on or off? See Two Quick Presses, Part 2: The Widget Bar.
Here it is: the one and only real button on the front of this phone. Push it to summon the Home screen, which is your gateway to everything the iPhone can do. (Details on the Home screen appear on The Home Screen.)
Having a Home button is a wonderful thing. It means you can never get lost. No matter how deeply you burrow into the iPhone software, no matter how far off track you find yourself, one push of the Home button takes you all the way back to the beginning.
As time goes on, Apple saddles the Home button with more and more functions. It’s become Apple’s only way to provide shortcuts for common features; that’s what you get when you design a phone that only has one button. In iPhone Land, you can press the Home button one, two, or three times for different functions—or even hold it down for a moment. Here’s the rundown.
One Press: Wake Up
Two Quick Presses: Task Switcher
If you press the Home button twice quickly, the screen dims, and the current image on it slides upward—to reveal the task switcher strip at the bottom. This feature is new in iOS 4, and was a lonnng time in the making. It’s the key to the iPhone’s new multitasking feature.
What you see here are icons of the four programs you’ve used most recently. Each time you swipe your finger to the left, you bring more icons into view, representing programs you opened less and less recently.
The point is that with a single tap, you can jump right back into a program you had open, without waiting for it to start up, show its welcome screen, and so on—and without having to scroll through 11 Home screens trying to find the icon of a favorite app.
In short, the task switcher permits, for the first time on the iPhone, a way to jump directly to another app, without a layover at the Home screen first.
This task switcher is the only visible element of iOS 4’s new multitasking feature, which is described in delicious detail on The Task Switcher. Once you get used to it, that double-press of the Home button will become second nature—and your first choice for jumping among apps.
Instead, it triggers your choice of shortcuts: to the Favorites speed-dial list, to the iPod controls, to the camera mode, or to the Spotlight search function. You choose which feature you want to dedicate the double-press to in Settings. For details, download the free PDF appendix to this chapter, “Redefining the Home Button Double-Press.” It’s available on this book’s “Missing CD” page at www.missingmanuals.com.
Two Quick Presses, Part 2: The Widget Bar
If you summon the task switcher and then drag your finger to the right, the task switcher reveals a set of four hidden controls. These go by the name of widgets, meaning that they’re not quite as full-blown as actual apps, but they still get their own icons. Here’s what they do, left to right:
Rotation lock. When you tap this button, the screen no longer rotates when you turn the phone 90 degrees. The idea is that sometimes, like when you’re reading an ebook on your side in bed, you don’t want the screen picture to turn; you want it to stay upright relative to your eyes, even though you’re lying down. (A little icon appears at the top of the screen to remind you why the usual rotating isn’t happening.)
The whole thing isn’t quite as earth-shattering as it sounds—first, because it locks the image only one way: upright, in portrait orientation. You can’t make it lock into widescreen mode. Furthermore, there aren’t that many apps that rotate with the phone to begin with. But when that day comes when you want to read in bed sideways, your iPhone will be ready. (Tap the button a second time to turn rotating back on.)
, , These controls govern music playback in whatever program is playing music in the background. They’re exactly the same as the equivalent buttons in the iPod app itself (Controlling Playback (Music))—but these are always two Home-button presses away, no matter what program you’re in. You can skip a horrible song quickly and efficiently without having to interrupt what you’re doing.
Music-app button. Finally, the app icon here represents your iPhone’s iPod app, or the Pandora Internet radio app, or whatever program is playing music in the background at the moment. Once again, the idea is to give you a quick shortcut when you want to switch albums, songs, or podcasts, so you don’t have to meander back to the Home screen.
Three Presses: VoiceOver or White-on-Black
In Settings→General→Accessibility, you can set up a triple-press of the Home button (iPhone 4 or 3GS) to turn accessibility features on or off: VoiceOver (VoiceOver) or white-on-black type (VoiceOver). If you choose Ask, then a triple-click summons three buttons: VoiceOver, White on Black, and Zoom (White on Black).
One Long Press: Voice Control
The Home button has one final trick: If you hold it down for about 3 seconds, you open up the voice control feature. Here, you can dial by speaking a name or number, or control music playback. Details on Voice Control.
The Home button is also part of the force quit sequence—a good troubleshooting technique when a particular program seems to be acting up. See Reset: Six Degrees of Desperation.
Silencer Switch, Volume Keys
Praise be to the gods of technology—this phone has a silencer switch (shown on Sleep Switch (On/Off))! This tiny flipper, on the left edge at the top, means that no ringer or alert sound will humiliate you in a meeting, a movie, or church. To turn off the ringer, push the flipper toward the back of the phone. (On models prior to the iPhone 4, doing so exposes an orange dot, to remind you that you’ve turned on your silencer.)
Even when silenced, the iPhone still makes noise in certain circumstances: when an alarm goes off; when you’re playing iPod music; when you’re using Find My iPhone (Find My iPhone); when you’re using Voice Over (VoiceOver); or, sometimes, when a game is playing. Also, the phone still vibrates when the silencer is engaged, although you can turn this feature off; see Notifications.
No menus, no holding down keys, just instant silence. All cellphones should have this feature.
With practice, you can learn to tell if the ringer is on while the iPhone is still in your pocket. That’s because when the ringer is on, the switch falls in a straight line with the volume keys. By swiping your thumb across these controls from front to back, you can feel whether the silencer switch is lined up or tilted away. (It’s a lot harder to tell on the iPhone 4.)
Below the silencer, still on the left edge, are the volume controls—a single up/down rocker switch or, on the iPhone 4, separate metal + and – buttons. The volume controls work three different ways:
Either way, a corresponding volume graphic appears on the screen to show you where you are on the volume scale.
The Bottom and the Back
On the bottom edge of the iPhone, Apple has parked three important components, none of which you’ll ever have to bother with: the speakerphone speaker, the microphone, and, directly below the Home button, the 30-pin connector that charges and syncs the iPhone with your computer.
The speakerphone isn’t very loud, because it’s aimed straight out of the iPhone’s edge, away from you. But if you cup your hand around the bottom edge, you can redirect the sound toward your face, for an immediate boost in volume and quality. That’s the one and only payoff for knowing what’s down here.
On the back of the iPhone, the camera lens appears in the upper-left corner. On the iPhone 3G and 3GS, the back is shiny hard plastic, in black or white; on the iPhone 4, it’s the same hardened glass that’s on the front. (For those scoring at home, Apple asserts that it’s “aluminosilicate glass, chemically strengthened to be 30 times harder than plastic, more scratch resistant, and more durable than ever.”)
And why are recent iPhone backs made of plastic or glass, and not metal, like the original iPhone? Because radio signals can’t pass through metal. And there are a lot of radio signals in this phone. All told, there are 10 different radio transceivers inside: four each for the standard GSM frequencies; three for the three 3G frequencies; and one each for WiFi, Bluetooth, and GPS.
iPhone 4 Special Bits
On the back, next to the camera lens, there’s a flash—a tiny LED that provides illumination in low light, provided your subject isn’t very far away. (It also can stay on when you’re shooting video.)
On the top edge, there’s a tiny pinhole next to the headphone jack. This, believe it or not, is a microphone. It’s the key to the iPhone 4’s noise-cancellation feature. It listens to the sound of the world around you, and pumps in the opposite soundwaves to cancel out all that ambient noise. (It doesn’t do anything for you—the noise cancellation affects only what the other guy hears, whomever you’re talking to on the phone. Then again, you’ll probably find that your end of the conversation sounds pretty good, too, since the sound chambers on the iPhone 4 were redesigned for better acoustics.)
On the front, the iPhone 4 has a second camera. That tiny hole to the left of the earpiece speaker slot is, in fact, a front-facing camera. Its primary purpose is to let you conduct video chats using the FaceTime feature (FaceTime), but it’s also handy for taking self-portraits or just checking to see if you have spinach in your teeth.
More on the iPhone’s cameras in Chapter 6.
Apple is so proud of it. This stainless-steel band is an Apple-concocted alloy, claimed to be five times as strong as steel. It’s the primary structural component of the phone—everything else is attached to it.
But this band is also part of the iPhone’s antenna, and that’s where the controversy begins; see About the Outline.
In the Box
Inside the minimalist box, you get the iPhone, its earbud/mike cord, and these items:
The charging/syncing cable. When you connect your iPhone to your computer using this white USB cable, it simultaneously syncs and charges. (See Chapter 12.)
The AC adapter. When you’re traveling without a computer, you can plug the dock’s USB cable into the included two-prong outlet adapter, so you can charge the iPhone directly from a wall socket.
You may have noticed one standard cellphone feature that’s not here: the battery compartment door.
The battery isn’t user-replaceable. It’s rechargeable, of course—it charges whenever it’s connected via the USB cable—but after 300 or 400 charges, it will start to hold less juice. Eventually, you’ll have to pay Apple to install a new battery (Out-of-Warranty Repairs). (Apple says the added bulk of a protective plastic battery compartment, a removable door and latch, and battery-retaining springs would have meant a much smaller battery—or a much thicker iPhone.)
Finger Tips. Cute name for a cute fold-out leaflet of iPhone basics.
What you won’t find in the box (because it wouldn’t fit) is a CD containing the iTunes software. You’re expected to have a copy of that on your computer already. In fact, you must have iTunes to use the iPhone (Chapter 12).
If you don’t have iTunes on your computer, then you can download it from www.apple.com/itunes.
Seven Basic Finger Techniques
The iPhone isn’t quite like any machine that came before it, and operating it isn’t quite like using any other machine. You do everything on the touchscreen instead of with physical buttons. Here’s what you need to know.
You can’t use a fingernail or a pen tip; only skin contact works. (OK, you can also buy a special iPhone stylus. But a fingertip is cheaper and much harder to misplace.)
When you’re zoomed into a map, Web page, email, or photo, you can scroll around just by sliding your finger across the glass in any direction—like a flick (described below), but slower and more controlled. It’s a huge improvement over scroll bars, especially when you want to scroll diagonally.
In some situations, you’ll be asked to confirm an action by sliding your finger across the screen. That’s how you unlock the phone’s buttons after it’s been in your pocket, for example. It’s ingenious, really; you may bump the touch screen when you reach into your pocket for something, but it’s extremely unlikely that your knuckles will randomly slide it in just the right way.
You also have to swipe to confirm that you want to turn off the iPhone, to answer a call on a locked iPhone, or to shut off an alarm. Swiping like this is also a great shortcut for deleting an email or a text message.
A flick is a faster, less-controlled slide. You flick vertically to scroll lists on the iPhone. You’ll discover—usually with some expletive like “Whoa!” or “Jeez!”—that scrolling a list in this way is a blast. The faster your flick, the faster the list spins downward or upward. But lists have a real-world sort of momentum; they slow down after a second or two, so you can see where you wound up.
At any point during the scrolling of the list, you can flick again (if you didn’t go far enough) or tap to stop the scrolling (if you see the item you want to choose).
Pinch and Spread
Apple uses the oxymoronic expression pinch out to describe that move (along with the redundant-sounding pinch in). In this book, the opposite of “pinching” is “spreading.”
Once you’ve zoomed in like this, you can zoom out again by putting two fingers on the glass and pinching them together.
Double-tapping is actually pretty rare on the iPhone, at least among the programs supplied by Apple. It’s not like the Mac or Windows, where double-clicking the mouse always means “open.” Because the iPhone’s operating system is far more limited, you open something with one tap.
A double-tap, therefore, is reserved for three functions:
In the Safari (the Web browser), Photos, and Google Maps programs, double-tapping zooms in on whatever you tap, magnifying it.
In the same programs, as well as in Mail, double-tapping means “restore to original size” after you’ve zoomed in.
When you’re watching a video (or recording one on the iPhone 4), double-tapping switches the aspect ratio (video screen shape); see Zoom/Unzoom.
This weird little gesture crops up in only one place: Google Maps. It means “zoom out.” To perform it, tap once on the screen—with two fingers.
Charging the iPhone
The iPhone has a built-in, rechargeable battery that fills up a substantial chunk of its interior. How long one charge can drive your iPhone depends on what you’re doing—music playback saps the battery least, Internet (especially 3G Internet) and video sap it the most. But one thing is for sure: Sooner or later, you’ll have to recharge the iPhone. For most people, that’s every other day or every night.
You recharge the iPhone by connecting the white USB cable that came with it. You can plug the far end into either of two places to supply power:
Your computer’s USB jack. In general, the iPhone charges even if your computer is asleep.
The AC adapter. The little white two-prong cube that came with the iPhone connects to the end of the cradle’s USB cable.
Unless the charge is really low, you can use the iPhone while it’s charging. If the iPhone is unlocked, then the battery icon in the upper-right corner displays a lightning bolt to let you know that it’s charging. If it’s locked, pressing the Home button shows you a battery gauge big enough to see from space.
Battery Life Tips
If you were an optimist, you’d point out that when these phones are using AT&T’s 3G network, they get longer battery life than any other 3G phone. You’d also extol the iPhone 4’s even better battery, which goes about 16 percent longer than the 3GS’s.
If you were a pessimist, you’d observe that the 3G/3GS and 4 models get only 5 hours and 7 hours of talk time, respectively, compared with 8 hours on the original iPhone. And that if you’re not careful, you might not even make it through a single day without needing a recharge.
So knowing how to scale back your iPhone’s power appetite could come in extremely handy.
The biggest wolfers of electricity on your iPhone are its screen and its wireless features. Therefore, these ideas will help you squeeze more life out of each charge:
Dim the screen. In bright light, the screen brightens (but uses more battery power). In dim light, it darkens.
This works because of the ambient-light sensor that’s hiding behind the glass above the earpiece. Apple says it experimented with having the light sensor active all the time, but it was weird to have the screen constantly dimming and brightening as you used it. So the sensor now samples the ambient light and adjusts the brightness only once—when you unlock the phone after waking it.
You can use this information to your advantage. By covering up the sensor as you unlock the phone, you force it into a low-power, dim-screen setting (because the phone believes it’s in a dark room). Or by holding it up to a light as you wake it, you get full brightness. In either case, you’ve saved all the taps and navigation it would have taken you to find the manual brightness slider in Settings.
Turn off 3G. This is the biggie. If you don’t see a icon on your iPhone’s status bar, then you’re not in a 3G hot spot (A Tale of Three Networks), and you’re not getting any benefit from the phone’s battery-hungry 3G radio. By turning it off, you’ll double the length of your battery. The iPhone 3G/3GS goes from 5 hours of talk time to 10; the iPhone 4 goes from 7 hours to 14!
To do so, from the Home screen, tap Settings→General→Network→Enable 3G Off. Yes, this is sort of a hassle, but if you’re anticipating a long day and you can’t risk the battery dying halfway through, it might be worth doing. After all, most 3G phones don’t even let you turn off their 3G circuitry.
Turning off 3G has another huge, huge benefit: It forces the phone to use AT&T’s older, but much larger, non-3G cellular network. It’s like switching from AT&T to Verizon on a per-call basis. Often, the result is that you can now place calls when you couldn’t before. Next time you’re getting a lot of dropped calls, remember this trick—and marvel.
Turn off WiFi. If you’re not in a wireless hot spot, you may as well stop the thing from using its radio. From the Home screen, tap Settings→Wi-Fi→Off.
Or at the very least tell the iPhone to stop searching for WiFi networks it can connect to. Carrier has the details.
This feature is designed for people who have signed up for one of AT&T’s capped data plans (Activation), meaning you have to monitor how much Internet data you’re using each month. If you discover that you’ve used up almost all of your data allotment for the month, and you don’t want to go over your limit (and thereby trigger an overage charge), you can use this option to shut off all data. Now your phone is just a phone.
Turn off the phone, too. In Airplane mode, you shut off both WiFi and the cellular radios, saving the most power of all. See Airplane Mode.
Turn off Bluetooth. If you’re not using a Bluetooth headset, then for heaven’s sake shut down that Bluetooth radio. In Settings, tap General and turn off Bluetooth.
Turn off GPS. If you won’t be needing the iPhone to track your location, save it the power required to operate the GPS chip and the other location circuits. In Settings, tap General, then Location Services, and turn off Location Services.
Turn off “push” data. If your email, calendar, and address book are kept constantly synced with your Macs or PCs, then you’ve probably gotten yourself involved with Yahoo Mail, Microsoft Exchange (Chapter 14), or MobileMe (Chapter 13). It’s pretty amazing to know that your iPhone is constantly kept current with the mother ship—but all that continual sniffing of the airwaves, looking for updates, costs you battery power. If you can do without the immediacy, then visit Settings→Mail, Contacts, Calendar→Fetch New Data; consider turning off Push and letting your iPhone check for new information, say, every 15, 30, or 60 minutes.
Turn off the screen. On the iPhone 3GS and iPhone 4, you can actually turn off the screen, rendering it totally black and saving incredible amounts of battery power. Of course, you now have to learn the VoiceOver talking-buttons technology to navigate and operate the phone; see VoiceOver.
Last battery tip: Beware of 3-D games and other add-on programs, which can be serious power hogs. And turn off EQ when playing your music (see iPod).
The Home Screen
Icons. Each icon represents one of your iPhone apps (programs): Calculator, Maps, Camera, and so on. Tap one to open that program.
Your iPhone comes with about 20 icons preinstalled by Apple; you can’t remove them. The real fun, of course, comes when you add to the starter set by downloading more apps from the App Store (Chapter 7).
Badges. Every now and then, you’ll see a tiny, round, red number “badge” on one of your app icons. It’s telling you that something new awaits: new email, new text messages, new chat entries, new updates for the apps on your iPhone. It’s saying, “Hey, you! Tap me!”
The standard Home screen can’t hold more than 20 icons. So where are all your games, video recorders, and tip calculators supposed to go?
The little white dots are your map. Each represents one Home screen. If the third one is “lit up,” then you’ re on the third Home screen.
And if you ever scroll too far away from the first Home screen, here’s a handy shortcut: Press the Home button (yes, even though you’re technically already home). That takes you back to the first Home screen.
The very first dot, at the far left, is actually a tiny magnifying glass. It represents the Spotlight (search) screen described on Spotlight: Global Search. It’s always waiting for you “to the left” of all the other Home screens.
The Dock. At the bottom of the Home screen, a row of four exalted icons sit on what looks like a polished glass tabletop. This is the Dock—a place to park the most important icons on your iPhone. These, presumably, are the ones you use the most often. That’s why Apple starts you off with the Phone, Mail, Safari (Web), and iPod icons.
What’s so special about this row? As you flip among Home screens, this Dock never changes. You can never lose one of your four most cherished icons by straying from the first page, so they’re always handy.
The background. In iOS 4, you can replace the traditional black background (behind your app icons) with a photo. Now, a complicated, busy picture won’t do you any favors—it will just make the icon names harder to read—so Apple provides a selection of handsome, relatively subdued wallpaper photos. But you can also choose one of your own photos.
For instructions on changing the wallpaper, see Photo Wallpaper.
It’s easy (and fun!) to rearrange the icons on your Home screens. Put the most frequently used icons on the first page, put similar apps into folders, reorganize your Dock. Full details are on Organizing Your Apps.