Let's face it, tracking down a lost bag at the airport is a pain-in-the-ass. While airlines will often compensate you with money and new clothes for your troubles, the experience is certainly not pleasant. Delta is now attempting to further reduce the number of lost bags through its real-time luggage tracker in the latest version of its mobile app. The Next Web reports: The feature apparently cost $50 million to build. It allows you to see where your stuff is -- provided that it's at one of the 84 airports that support Delta's new tracking tech. Here's how it works. All bags will get a Radio Frequency Identification (RFID) tag. This allows Delta to track them in real-time using radio waves. Scanners positioned throughout the baggage system will allow Delta to monitor where the bag is, and relay that information to the passenger. Delta has traditionally been one of the best airlines when it comes to handling baggage. During 2012, it lost only 200,000 bags. That sounds like a lot, but bear in mind it carried 98 million passengers during the same period. You can try the feature on your next Delta flight by grabbing the app from Google Play and the App Store.