Edit: The next three reviews will cover Nano Panda, Burn the Rope, and Cut the Rope (all recently release puzzle games that hit the same part of the brain). The first two are currently available in the Android Market and Cut the Rope is set for imminent release on the Android Market and can be obtained from getjar.com until then.
Now if all you had to do was launch pandas then that wouldn't be too interesting so let's add that when multiple pandas are in play they attract one another. It's easier to understand when you see it, but the attraction is basically like gravity. If the pandas are close they attract and swing around in a small ball, but if they were far away they zip towards and right by one another covering a much larger area. It's this swinging and chaining of panda that allows you to get them to knock off all of the bad guys. Add that the screen also contains spiked areas that kill off your pandas upon contact and you've got yourself a game.
The graphics of Nano Panda are fine for a puzzle game as is the sound. No glaring deficiencies and nothing earth shattering either. The controls are simple... touch a launcher to release a panda. The key to the game is figuring out the order and timing in which to release them. As you would expect, the game comes with several confidence builder puzzles to show how to launch and then how the pandas attract one another, but soon you'll get to stages that are quite difficult.