Android Studio: creating Android Virtual Device AVD

Why do we need AVD?

To be honest most of my Android testing happens on the real devices, however sometimes you need to test on a device with different screen size, different resolution (dpi) or limited memory or network bandwidth.

Example AVD Settings

One of my favorite emulator settings is the 10.1 inch tablet with mdpi resolution, it it relatively light weight and works pretty well.  

Starting AVD with the correct scale for your screen size.

It is essential that when you start the emulator of e.g. 10.1 inch tablet, it is actually 10.1 inch (diagonally) on your screen - you should measure it with a ruler. If the screen is too small you will design all the elements too big, if the emulator is too big, the UI will be too small on the real device.