Does anyone wish there were an app (iPhone or Android) that you haven't been able to find? In my case, I wish there were an iPhone app to teach European road signs. Last week was my first time to rent a car on the Continent, and I was wishing I had studied all the symbols before I hit the road. The app might be in the form of a multiple-choice quiz. It could show not only signs, but also painted pavement markings. Also, a photo of a bank of toll booths on a toll road with the question: "Which booth accepts cash and makes change?" Are there any other apps that should exist, but you haven't found them yet?