How to use Android's Home Screens
Physical layout of an Android Device
Android devices use touch screens. Most have no physical keyboard, but you can also find a number of models with a slide-out keyboard or an attachable keyboard dock for tablets. Around your device you'll find the ususal physical buttons for power on/off, volume on/off, audio connector, micro-USB (for charging, connecting to a PC and in some devices connecting to HDMI using an adapter). You'll typically have both back- and front-facing cameras.
Home Screen Layout and Operations
You just have to press the screen gently, no need to push hard, when you operate the device. After you've unlocked the device as described in the previous chapter then you'll be presented with the home screen. In Android you have actually 3-7 home screens, depending on your Android device model. You move between them by sweeping the screen to the right or to the left. The one in the middle is often THE Home screen.
Remember, Android is highly customizable, many manufactureres start by putting a "skin" on top of "vanilla" Android. You're not just watching a set of static icons, like on some other phones. The user can change many things, for example add widgets with live data (for example: weather, stocks, news), live wallpapers, apps, folders, etc. So what you'll see here are examples of home screens, but the general layout principles holds across all of them. Each home screen has a number of columns and rows, depending on the screen size and resolution. For a phone the grid may be 4*4, a tablet may have its home screens divided into a grid with 8 columns and 7 rows.
Galaxy Nexus Layout (Android 4)
Let's start by looking at the Galaxy Nexus, which is a Google-designed phone using "vanilla" Android 4. On the top of the screen you'll find the Notification & Status Bar. This is where your phone can give you information about new emails, SMS, missed calls, as well as status information, e.g. the time, battery level etc. You can see the details by sweeping the Notification Bar downwards, like a drop down curtain. When you scroll to the left or right among the home screens, the Notification Bar is always there at the top. The Notification Bar is described in more detail in the next chapter.
Below that is the Google Search Box. Just tap it and an on-screen keyboard will pop-up and you can enter searches. The middle portion is where you can place widgets, shortcuts to apps and folders. In this example we have a widget for a transparent analog clock, then an app icon (serving as a shortcut) to the camera app. To the right of that you have a folder with a number of Google apps that comes pre-loaded with your device.
Below the main part of the screen comes the Apps Dock. You can think of it as a Favorites tray. When you scroll left or right to other home screens, the Apps Dock will remain in place (just like the Notification bar) since it usually points to the most commonly used apps. In this example we have 5 items, from left to right: Phone dialer, Internet browser, Apps Drawer (which will show all your installed apps), Messenger and Camera.
At the bottom you have on-screen buttons, for the Galaxy Nexus they are: Return, Home and Recent apps, which makes it easy to do multi-tasking on Android.
Nexus S Layout (Android 2.3)
This is the older version of Android, also "vanilla". Although the design is different, the functions are quite similar. Again, at the top you have the Notification & Status Bar and the Google Search Box. In the middle section you'll find the app icons for the standard Google apps for Gmail, Maps, YouTube and the Play Store (Android Market), from which you can download apps and widgets.
The Apps Dock has three icons: Phone dialer, Apps Drawer and Internet browser. To the left and right of the Apps dock you'll find small dots that gives an alternative way to move to the left and right home screens, instead of sweeping left or right.
At the bottom of the phone we find the Navigation Buttons that were described in a previous chapter. If you long-press the home button you will see a list of the recent apps you've been running,
Other Home Screen ExamplesLet's take a look at some of the variations.
As you can see all three have a Notification Bar at the top. Both the Android 4.0 and Samsung's home screens have a search box. You can see widget examples on all three: Android 4.0 has an analog clock in the middle, Samsung's and HTC's have a widget that shows the weather and a date & time. Android 4.0 uses "soft" buttons for navigation, Android 4 has only 3 navigation buttons. The search button and menu buttons are gone. But you have a new button that gives you a list of the most recent apps, which makes multitasking very easy. The examples from Samsung and HTC use physical buttons that are not on the screen. Samsung's main home screen is actually the leftmost screen, you can jump between screens by pushing one of the seven dots just above the Apps Dock.
At the top-left of the screen you see the Search Box, you just tap it and a keyboard will appear on the screen. You can also tap the microphone to use voice commands. In the top-middle you see 5 dots which indicate on which home screen you're at. At the top-right you have the icon for the App Drawer (App Tray). If you tap it you will get to the App Drawer screen where you have access to all your installed apps. The bottom-right area is the Notification area, just tap the area (e.g. the clock) and your notifications will pop-up. At the bottom-left is the System Bar with the navigation buttons (Return and Home) plus the Recent Apps button. Some apps may also display a Menu button next to the Recent Apps button. Tapping it will show relevant menu options for that app.
You can customize the large area in the middle of the screen all you want. In this example we have 3 widgets (weather, new emails and date). Below them are 8 app icons, you just tap any to start that app.