Google Maps iOS - Shaking the device allows the user to submit feedback.
Google Maps - When zooming in to the maximum, the zoom in button merges with the street view button indicating that the next zoom level is with street view.
/via Toby Adams
Google maps - The iPhone icon represents the actual location of the Apple headquarters in Infinite Loop Cupertino.
/via Jan Semler
Google street view - The icon changes to a skier when viewing a piste. Try picking it up as well.
Maps - the subtle differences in map designs. See link below for detailed analysis.