Fast Fifteen is a free card game developed by Zenlookapps.com for Android devices. The game is designed to test your mental agility and ability to solve puzzles under time pressure. The objective of the game is simple - find sets of cards that add up to 15 or tap 4-of-a-kind 10's, jacks, queens, kings as quickly as possible.

The game features a user-friendly interface with an easy-to-understand gameplay mechanism. You can tap on two or more cards that add up to 15 to remove them from the board. You can also tap on four cards of the same rank to remove them from the board. The game is divided into different levels, each with a different layout and difficulty level. As you progress through the levels, the game becomes more challenging, with more cards and less time to complete each level.

Overall, Fast Fifteen is a fun and challenging card game that will keep you entertained for hours. It's a great way to improve your mental skills and pass the time. If you're a fan of card games and puzzles, then Fast Fifteen is definitely worth a try!