Coming December 13 to iOS and Android from BulkyPix and developer int13, AR Defender 2 allows you to play 40 levels of tower defense anywhere you can fit a printed AR marker card.
While we wait for augmented reality to be put to use doing something useful and practical, games like AR Defender 2 will keep the technology alive. Up to four players can team up to take on mechanical enemies as they storm their base, which can be located wherever you feel like sticking a little white card with some black dots printed on it. Outside on the grass, inside on your desk; tattoo the marker on your arm and then try and play with one hand.
All 40 levels of the game can be played outside of AR mode, and it's not a bad little tower defense game on its own. Should be fun until saying "Hey look, I'm playing a game on XXXX" loses its charm.