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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: ReturnHome and Recent apps, which makes it easy to do multi-tasking on Android.

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