Allied Star Police is a pretty good twist on the tower defense theme and you can get it for iOS here for free. This is a PopCap game designed by ten-year-old Owain Weinert.
PopCap met Owain in April when Make-A-Wish Foundation® of Alaska & Washington told us about his wish to make a video game. Owain (which means “little warrior” in Welsh) was diagnosed with pre-B Acute Lymphocytic Leukemia last year and has gone through lots of difficult treatments. But his dad said that what he really wanted was to hang out with “real game designers”. So we volunteered to help Owain make his video game during PopCamp. PopCamp is a unique time here when folks can tinker around with interesting ideas, learn lots of new stuff and share it with everyone else at the end of the week.
More on Destructoid including this video:
I finished the game this afternoon. There are only 3 levels but the last one is a real war of attrition. Took me just over 11 minutes to finish that last level!