Can Android be used for home automation ?
Sure, so can C#, php, basic and any other language. The question really is what hardware are you attempting to interface with ?
You can as an example get a light bulb with built in blue tooth Yes you can
] so as long as you can find out the specs or if the company has already provided a android app you can control your lights with your phone.
Perhaps starting with a site like Instructables
] would be a good place to look.
Hope it helps