There's almost an infinite number of combinations of possibilities when it comes to creating home automation projects, and one minimal example has been demosntrated by Instructables member Samuel LIU who shows how to control AC relays with his iPhone and a Raspberry Pi.
The communication between the two devices is via a local WiFi router, and both the iPhone and Pi are running python scripts to create an interface on the phone and for the Pi to interpret the incoming control requests and switch a GPIO pin for relay control. A quick demonstration is shown in the following video:
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This is a great way to add your own electronic components, circuitry, sensors or other devices to your Raspberry Pi model A+, B+ or 2 Model B - any of the current Raspberry Pis with a 40 pin GPIO header. The PiBreak Plus also includes a GPIO female header to solder yourself, and a pair of nuts, bolts, washers and spacers to ensure a a great fit.
And in the Freetronics fashion we've used a quality gold-plated (ENIG) PCB for durability, brought out all the power rails along with the GPIO next to the prototyping area to make adding circuits a breeze. Furthermore the pinouts are labelled on both the top and bottom of the PCB to save time referencing the right GPIO pins. For more information and to order - visit the PiBreak plus page now!