I think there are two killer apps on the iPhone. Mobile safari with multi-touch and the gmaps app with multi-touch. I don't use any other app on a daily (or e

I think there are two killer apps on the iPhone. Mobile safari with multi-touch and the gmaps app with multi-touch. I don't use any other app on a daily (or even weekly) basis with the possible exception of the Yelp app and the WeatherBug app.