Zombies, Run! is an awesome game, but if you're looking for other similar games here is a list of apps that offer encouragement to exercise by some form of gamification
Summary 
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| Name | Running | Walking | Bicycle | Elliptical | Strength |
|---|---|---|---|---|---|
| BattleSuit Runner Fitness (discontinued) | Outside Only | Outside Only | Outside Only | ||
| BitGym | Treadmill | Treadmill | Static Only | Yes | |
| CityStrides | Outside Only | Outside Only | |||
| Code Runner | Outside Only | Outside Only | Outside Only | ||
| Fit For Battle | Yes | Yes | ? | ? | |
| Fit Freeway (discontinued) | Treadmill | Treadmill | Static Only | ||
| Ingress | Yes | Yes | Yes | ||
| Pokemon Go | Yes | Yes | Yes | ||
| Run An Empire | Outside Only | Outside Only | Outside Only | ||
| Runtastic Story Running | Yes | Yes | Yes | Yes | |
| SpecTrek | Outside Only | Outside Only | Outside Only | ||
| Step Buy Step | Yes | Yes | |||
| The Walk | Yes | Yes |
BattleSuit Runner Fitness Edit
Running adventure game following an alien invasion story where the runner is the user of a battle suit. Runs gain materials to upgrade the suit. Included 'zombie chase' style sprints. Speed can affect the story
Free version has limited number of missions. Full version currently has only 9 missions, more are promised in future.
The iOS app appears to be abandoned and no longer supports modern iOS.
BitGym Edit
Virtual speed-interactive tours of real-life locations. Only works on static cardio machines (eg treadmill, elliptical or stationary bike).
CityStrides Edit
Not really an app but maps every street you have run by connecting to other running services such as Runkeeper and Strava. Encourages you to run every street in your town/city
Code Runner Edit
Espionage adventure that uses GPS to guide you to secret real-world locations for spying, hacking and sabotage
Fit For Battle Edit
Fit for Battle is an interactive audio based running app where you are the hero at the centre of an epic fantasy adventure. Each run is turned into a quest where your performance directly influences the direction of the story. Currently available for iPhone with Android coming soon
Fit Freeway Edit
Race to keep your car in the race, keep up the pace to reach checkpoints. Only works on static cardio machines (eg treadmill). Seems to be discontinued by owners BitGym
- iPhone or iPad
Ingress Edit
Designed for walking, but could be run, you locate 'portals' in real-world locations and other items of use to your 'faction'
Pokemon Go Edit
Designed for walking but could be any form of locomotion, you locate and attempt to catch Pokemon locate Pokestops and gyms in real-world locations. Very similar to Ingress
Run An Empire Edit
Capture areas of the city by running around them. Sounds like Ingress but with running.
Runtastic Story Running Edit
Part of the Runtastic app, you can download stories to accompany your run such as escaping from Alcatraz. There is also an exclusive Maze Runner tie-in. Plays like an audio book with accompanying music
SpecTrekom/store/apps/details?id=com.runtastic.android Edit
Designed for walking, but could be run, you hunt for ghosts at specific locations and use your phone to 'see' the ghosts and hopefully catch them. SpecTrek Light is free (unsure what the limitation is)
Step Buy Step Edit
Walking adventure game by the makers of Zombies, Run!
The Walk Edit
Another walking adventure game by the makers of Zombies, Run! You walk the length of the UK with a package that could save the world
