Introducing the Android Emulator, managing Android Virtual Devices (AVD) | Hello Android

The emulator available in the Android SDK is not just a tool that allows you to easily test applications without having to install it to a real device, or even having one. With the proper configuration it is possible to test situations which are hardly reproduced on a physical one.

After installing the android plugin and SDK in eclipse an icon is automatically placed on the toolbar to quickly access the Android SDK and AVD (Android Virtual Device) manager.

For an AVD you can set the

screen resolution
Android version
SD card size
and various hardware availability and properties such as GPS, RAM, accelerometer, camera, cache etc.

When you press the new hardware button, it pops this dialog to select the hardware and aftred adding it you can change value attribute for it. The value often is a boolen to set if the hardvare is available or not, but it can for example an integer to set the size for the RAM.

Of course it you set a hardware like GPS available on the emulator the running application will detect that it is available, but this 'virtual' GPS naturally can not provide a GPS coordinate on its own. Like we discussed it in a previous tutorial a coordinate can be sent by using telnet in the command line. This goes for similar hardware too.

All of this makes possible for example to test behavior of the application when SD card has not enough space, the memory runs low, or how does the user interface fit in different resolution.
The backwards compatibility is another important question. Each project has android versions meant to be compatible with. This can be validated easily since all the previous Android versions can be downloaded. It is an essential test, because the available API versions for development and the mostly used versions worldwide can greatly differ.