android.minSDKVersion is used to declare that devices running Android versions lower than this will not be able to install the application.

There are four buttons were available in Android device prior to version 3.0: Home, Back, Menu and Search

Android virtual device is an emulated android device, which is used to run the android application. This device gives the real feel of the android device.

The Activity class is the main building block of Android application. It represents a single screen of the application.

User interface or GUI is defined by Android using a combination of XML layout files and Java code.

There are four Android Project Folder Structure:

Widgets are like mini application that presents small chunks of data such as weather or unread email counts. It is like a application for small amount of data.

Properties window is not a part of Android Developer tool. The main components of ADT(Android Development tools) are:

The Dalvik Debug Monitor Server(DDMS) is a powerful tool for capturing the state of your application, including running thread counts, logs, object allocation and heap usage.

In the Android Version 4.0 and above, you can take the screen shots by pressing power button and volume down button at the same time.

Hierarchy viewer is used to display the full layout hierarchy of the application. The components of hierarchy viewer are: Left Sidebar, Tree View, Tree Overview and Layout View.

The res/ folder contains all the resources of our android app and this is where we declare the layout using XML>

The manifest contains essential information about our app that the android system needs. This includes the activities and services by app users.

Eclipse Integrated development environment is used to develop the Android project.

Here you have to set the “name” and “required” property of use-features tag to “android.hardware.touchscreen” and “true” respectively. For Example: <uses-features android:name=”android.hardware.touchscreen” android:required=”true” />