When the streets filled with zombies you jumped into a car and.... began doing many tasks.
Gears & Gut is one of the best car games these days. It’s very close to the legendary Carmageddon but for Androids. The graphics is so better and the game offers many and many details for improving your vehicle. Try various weapons as flame throwers, spikes, shooting things, blades,etc.
The tasks vary in some details but mostly, you have to clean cities from zombies, finding items or defeating special enemies.