If you are looking for a simple, yet challenging game for your Windows Phone take a look at Sketch Taxi.
Patterned after the video game Space Taxi, Sketch Taxi is sketched out much like Doodle Jump or Parachute Panic. You control a taxi as it flies around picking up fares. Along the way you have to avoid crashing into things which will send your taxi falling from the screen in ball of flames.
Sketch Taxi may not appeal to everyone but the graphics are nice and game play is challenging. Overall, Sketch Taxi is worth giving the trial a chance.