Labor mate is a typical great iPhone app in that it does one thing incredibly well. It times contractions. Press a button when the contraction starts, press again when it stops, and Labor Mate puts together a nice list of the frequency and duration. Think it's about to get real? Labor Mate will email the contraction log to your doctor for him or her to review. It will even update twitter and Facebook if you are the type who loves to over share!
My advice for all people who are pregnant is to go straight to the app store and spend the $0.99 for this perfect little app (and ask your wife before tweeting contraction information).