Great Game, but the upgrades...

I very much enjoy this game. I usually play to pass the time during my break on working hours. But, I will admit grinding for coins for the next upgrade becomes very tedious. But, I found a strategy to play it to gather lots of coins. Heres, how:

Save your Ammo! Although, you need to kill to gather coins. I found that saving my ammo usually keeps me in the game longer. Only use it when you really have too. And, thats when you see 2-3 zombies in a row in front of you on all 3 lanes. Also, if you see only 1 zombie in a lane let the character Melee it, and make sure not to get hit again until the zombie chasing you behind loses distance. Eventually, youll come up with some power ups to use and of course more ammo along the way.
Ive tried this strategy and gain 500 coins in 1 run. Maybe itll work for you?

Leviathan30z about Running Zombie War: Killing Dead - by Fun Games For Free