Family was spending a day on a isolated beach on The Cape and this shark app warned them about a Great White in the area....turns it out was right next to their boat. Cool story.
https://www.bostonglobe.com/metro/2016/07/26/new-app-helps-family-close-call-with-great-white/XrazDHvv5xnx64fCFZeaFO/story.html