RUN! Zombies are chasing you!

Your mission is to help the planet avoid a zombie apocalypse.

That's the motivation in Zombies, Run! 2, an app for iPhone and Android that challenges you to reach your goals through "Zombie Chase" interval training. 

In Zombies, Run! 2, you are inserted in a gripping storyline where you must achieve your fitness goals to move the story forward. Here you'll trade the usual encouraging and inspirational messages (like "you can do it" and "you really rocked today") for zombie-related messages ("they're right on your tail; don't look back!" and "they spotted you — run!").

This app is another example of "gamification" — using game theory and tactics to incent people and improve engagement. A proliferation of apps and devices now help connect you to your health — from tracking activity and sleep to counting calories and nutritional breakdown of food.

If you fear zombies — and it will make you run faster, further and more often — this is the fitness app for you.