I create a project for control all your IR signal devices (TV,HI-Fi,A/C,Remote Lights,...) from android with this https://play.google.com/store/apps/details?id=power.remote.control free ads application.Android send bluetooth signal to arduino with bluetooth shield and arduino with IR led send IR signals to IR devices inside your room.You must decode IR signals from your device.For example i had decode my A/C Toyotomi and create a library IR pulses Toyotomi.Also you can control and arduino with connected relays or you can add remote control sockets and control lights,coffee maker,....Look and inside my site for more informations.