How to remote control a robot car via an android phone by using wifi to connect?

How to remote control a robot car via an android phone by using wifi to connect? please give me some idea about that. Thank you =(

http://lmgtfy.com/?q=arduino+wifi+android

The top two links both provide full source code on both ends. If you have specific programming questions about why they're doing something, or if the code you write has a bug in it, anybody on here would be happy to help.