Running on the emulator
Emulators are Android Virtual Devices (AVD) that we need to configure to run our Android apps.
Step 1
Open the AVD Manager as in:
Step 2
Click on the New Button to add a new device, and configure your device settings.
Step 3
There will be a result window showing all the configurations you had chosen on the previous screen.
Step 4
Press "Ok" and you will see your device listed in there and now you can close this window now.
Step 5
Run your Android app project from Eclipse and if there is only one AVD configured it will automatically deploy the app to it else a window will appear to choose your AVD. The Emulator will start.
Running on the Device
An Android app can be directly deployed on the Android device, for this a few configurations are needed.
Step 1
Set the application in the debug-able mode by setting the android:debuggable attribute of the <application>element to true. For ADT 8.0 this is done by default. (In our ADT we do not need to perform this step.)
Step 2
Enable USB debugging on your device.
For Android 3.2 or older go to Settings > Applications > Development and enable USB Debugging.
On Android 4.0 and newer, it's in Settings > Developer options.
Note: On Android 4.2 and newer, Developer options is hidden by default. To make it available, go to Settings > About in the phone and tap Build number seven times. Return to the previous screen to find the Developer options.
Step 3
Install USB drivers for your device so that the computer recognizes your device.
Step 4
Once set up and your device is connected via USB, install your application on the device by selecting Run > Run (or Run >Debug) from the Eclipse menu bar.
Cheers.