This app combines a number of fun factors. First, it's a sci-fi story of the Zombie Apocalypse. The program alternates Orson Welles-style story segments with songs from your chosen play list. Just load the story, pop on your headphones, and start running. The first mission begins a couple months into the end of the world as you fly into a survivor camp in a helicopter. You are shot down in the middle of zombie territory and must run to the camp, guided by the voice on the radio. Once safely inside, you're given the position of Runner 5. Other missions include picking up supplies, warning people of an impending attack, and discovering what caused the disaster. I'm about half way through Season One, and Season Two was just released this week. This is a great motivator to go out for another run so you can find out what happens next.
Second, it's an interval training program using an optional chase mode. When turned on, about once a mile you will hear, "Zombies approaching," followed by beeping to let you know how close they are. You need to run 20% faster for one minute to evade the zombies. I'm already an interval runner, so this is great for me. I don't usually use it on long runs, though, since I don't want to burn too much energy at once, but I love it for short runs.
There's also a couch-to-5k style companion app. It's not crucial to the story, but it does add some supplemental detail as well as give a good 8-week training for beginner runners. I haven't used it, being a more experienced runner, but I may just to try it out for fun.
Third, it's a Farmville-style game. As you run, the game will pick up supplies like batteries, canned food, and ammunition When you get back home, you can distribute your supplies to build up your survivor camp, deciding if you need to prioritize the hospital, armory, or housing first.
On top of that, it tracks your stats so you can see how well you're doing with your training. I just love it! And to make things extra-epic, I made my playlist the soundtrack to several big adventure movies: Lord of the Rings, Pirates of the Caribbean, and Star Wars. There's just nothing like hearing Sam say, "Watch out for zombies on your left," followed by Darth Vader's Theme, The Ride of the Rohirrim, or the March of the Dead Pirates.