Android :: How To Catch An Incomming Text Message?

I want to be able to control incoming text messages. My application is still on a "proof of concept" version and I'm trying to learn Android programming as I go. First my application need to catch incomming text messages. And if the message is from a known number then deal with it. If not, then send the message as nothing has happened to the default text message application. I have no doubt it can be done, but I still have some concern and I see some pitfalls at how things are done on Android. So getting the incomming text message could be fairly easy - except when there are other messaging applications installed and maybe the user wants to have normal text messages to pop up on one of them - and it will, after my application has had a look at it first. How to be sure my application get first pick of incomming text messages? And after that I need to send most text messages through to any other text message application the user has chosen so the user can actually read the message my application didn't need.