Source: http://lifehacker.com/build-your-own-voice-controlled-tv-unit-with-an-android-1611103727
Taking a little time to be a couch potato is sometimes just what the doctor ordered. If you want to maximize your laziness, this DIY setup from Jayvis Vineet Gonsalves lets you control your TV with your beautiful voice.
Gonsalves calls his project "Aergia," which is the name of the Greek goddes of laziness and sloth—fitting. With Aergia, you can control your TV, set top box, stereo, or any other device that uses an IR remote. All you need is an Arduino Uno, a Bluetooth module, some IR receivers, and a few other electronic parts. If you have an Android device, it only costs you $20 to build, requires minimal electronics knowledge, and just a little skill with a soldering iron.
Using your Android touch screen device you can power the TV on and off, change the channel, navigate menu settings, turn the volume up or down, and it has 12 additional buttons you can program for whatever you like. The best button of all, though: the speech recognition button. Tap that button and you can control the whole setup with your voice. For a list of parts, thorough instructions, and more information regarding voice commands, check the link below. Happy channel surfing!
Aergia: Android controlled TV Remote (with Speech Recognition) | Instructables