Greatist Bites examine what’s fun, weird, innovative, and downright interesting in health, fitness, and happiness — all in 250 words or less. Check out all recent Bites here.

The Walk

A mobile app that mashes up fitness tracking with an interactive spy story? What’s my cover and where do I get my top-secret instructions? Currently on sale for $3.99, The Walk is a new app from the creators of Zombies, Run! and funded by the United Kingdom’s Department of Health and National Health Services, developed to encourage people to exercise by walking more every day.

With 65 episodes and 800 minutes of audio, The Walk takes the gamification of fitness to a new level. Each IRL step you take moves you along the game’s interactive map, getting you closer to earning clues about your mysterious 500-mile journey. A counter tallies minutes moved, steps taken, average number of active minutes each day, and how much longer you’ll need to walk to unlock the next clue or audio clip. With a truly cool story and exciting, well-produced audio, making it to the next checkpoint to learn more about your shadowy journey is motivation to get to stepping.

Now, if you’ll excuse me, there’s been an explosion at Scotland’s Inverness train station. Communication and transportation are out across the country and I need to move this package before enemy agents catch on to me and this mission is rolled up.