The excellent Door Kickers and sequel Door Kickers: Action Squad are both 99c right now on the Google Play Store, down from $3.99 and $2.99 respectively.
Developed by Killhouse Games, Door Kickers is an acclaimed action strategy game in which you command a SWAT team infiltrating an enemy stronghold and killing everybody, preferably after kicking down a door.
Door Kickers is widely acclaimed on all platforms, thanks to its slick interface, clever level-design, open-ended gameplay, and well-judged difficulty. It’s well worth a buck.
Door Kickers: Action Squad is a fairly radical sequel, stripping away much of the tactical stuff and replacing it with raw side-scrolling action – though there are still Strategic Abilities to consider.
Both games are very well reviewed, with average review scores in excess of 4.5/5. They make a good pair, too, with two radically different takes on tactical combat, so you can buy them both without guilt.