Batscanner

The Batscanner is a device that was employed by Batman in Batman: Arkham Knight.

Design
It seemed to be an upgraded Remote Control Batarang, though was only employed when Batman needed to do a scan of a large area, notably the whole of New Gotham during his initial search for Scarecrow's Fear Toxin manufacturing location. It was also used when searching for microexplosives that the Riddler had planted into random thugs, and highlighted them in red.