I am helping my client to develop android app for their daily admin activities. The client does not want to user to spend working time to surf web, chat, play game and download app.

What are the steps I need to create a custom android ROM that will only let user to access mobile network and wifi setting ? Plus, once it is rebooted the app I develop will show automatically ?

Perhaps, there is an android app in the market that will allow me to do this ?