Keyless Entry System App

[Update: Jan 2013]

Intellacase is trying to do this exactly. Hope you raise all the funds you need. Help them at Kickstarter:
http://www.kickstarter.com/projects/intellacase/intellacase-the-worlds-smartest-phone-case

[Originally Posted: Oct 2011]

Need:

I have a smartphone and have a keyless entry system for my car. My wife keeps loosing the keys but (almost) never her iphone. Can we merge it in one?

Description:

Can we just include an App that works as my keyless entry system? How hard is that? Or maybe it is easier to have a case that includes the chip so it works.

Potential:

Again, cars 50M, maybe $20 for each system that will make it US$1B market.