Dear Abdulkawi,
The information given by tpetar is very much sure and I have tested that circuit in real. It works awesome. This can resolve your first query.
For MCU code , if you look at the algo its very simple. Any newbie can do it.
I can contribute regarding your third query.
If you want to us Android devices with your platform....here are 3 main interfaces
[1] Bluetooth - You can interface low cost Bluetooth DCE with your target MCU on which you will write code. Standard Eclipse bluetooth stack is available using which you can integrate
[2] Wifi - You can go with commercial low cost wifi modules . I will suggest CC3000 from TI [We have used for MSP430XX]
That can also give you best solution
[3] USB host - If you want much simpler solution. Go with FTDI's FT311D. It works very finely with android devices. It provided standard android host capability to your MCU to which android devices can be connected.
Last opetion can be web. Put a low cost GPRS module with MCU and develop web app.
That all can work for you.