@Richardxtc
You can do this in different ways. You can use the X10 hardware with compatible software like Homeseer(bit expensive) and install that on your pc at home. They have an app on the Android market called HSTouch that will then connect through the internet or internal Wifi to your homeseer server.
You can also use a new technology called Z-Wave, much more reliable than X-10 as it's a mesh networking protocol and wireless, bit more expensive though but it's got 2 way communications. You can still use the Homeseer software or you can use a Micasa Vera2 Z-Wave controller(device and software built-in,so no need for a pc) and they also have a web interface and app for Android, iPhone.