Android Application for Arduino


I am new to this and I'm doing this for my final year project. What I have is Android, Arduino Uno, Xbee Wi-Fi Shield, and XBee Wi-Fi Module. All I want is how to code in Android and Arduino. I understand that in X-CTU software, there are XBee Ip Address and Wi-Fi protocols(UDP/TCP). I tried to modify others work but not working. Can someone please help me. I just need to turn on and off the LED. I just need the start.