SERP Ranking Mobile App?

Has anyone developed a good iPhone app that shows SERP rankings for a user's websites? I'm surprised services like Serpbook don't have them, and I can't find anything on the app store but I might not be searching for it right. Does anyone know of an app that displays your rankings, or a service that has a mobile app?

I use "SEO Tool - check site position". Your search skills are must need improvements.