Neighborhood watch apps aren't just for civilian streets. The US Army has forged a deal with CloseWatch to use a mobile crime reporting app, iWatch Army, to prevent mass shootings and other crimes at over 20 domestic bases. The software forwards tips (based on the FBI's own crime codes) to the appropriate unit in less than 8 seconds, or faster than a 911 call. It also has its own notifications, so you can get an alert if there's a credible threat. While iWatch Army isn't meant to replace emergency services, it could be crucial to catching terrorists before they're ready to strike.