I should probably boycott developer Robomondo for all eternity after it subjected me to the hot garbage that was Tony Hawk: Ride. But I'll make an exception for its cute Halloween freebie, Monster Flash.
The game plops you in the centre of the screen, and then bombards you with waves of monsters, bats, vampires, and ghosts. Your only defence is to spin around in circles and zap the beasts with your torch.
There are special powers, and extra characters to unlock too. Monster Flash is not the deepest or most long-lasting game in existence, but a nice festive time-waster for Halloween. You can get it on iOS and Android, for free.