Today's Free App of the Day is Cogs
Originally $2.99

This is a well reviewed, well conceived and attractive puzzle game. Can you tell I liked it? I hadn't heard of it, though apparently it's been available through Google Play for some time.

From the product page: "Cogs is a ground-breaking puzzle game where players build increasingly complex machines using sliding tiles in 2D and 3D environments. It comes with 50 puzzles and three gameplay modes for a total of 150 unique challenges, totalling more than 10 hours of mind-bending gameplay. This award-winning game is perfect for puzzle fans of any age and ability!"

You get a set of tiles, some of which have gears or pipes on them in the levels I've played so far. You slide the gears, pipes or blank tiles to an open spot (the tiles have a wood-grain appearance, the open spot does not) with a goal of getting the golden gear to connect to the initial turning gear and thus turn. It's like those sliding tile games with the numbers one played as a child--you have to get them in the right order.

You get three ratings for each puzzle: completion, time and moves. You can get one, two or three stars in each case. You can see what the goals for each puzzle are by tapping on the Awards button on the description for that puzzle. Some of the puzzles are three dimensional--for example, the second puzzle is a cube. You can rotate the puzzle with two fingers as your connected gears must go around the sides of the cube. When you are successful, in the case of the second puzzle, a propeller starts to turn and the cube floats away. Fun!

It has replay value as you can try to get better times and lower number of turns. It can be played in airplane mode. It must be played in landscape mode but will rotate 180 degrees. A couple negative reviews cite the permissions--specifically the one that checks for device startup. Amazon's been on a good run lately--must be the holidays. Loved this game.

51 of 53 reviews are four stars and above.

These apps are compatible with the original Fire and with my Fire HDXs, both 7" and 8.9". To tell if an app works for your Fire HD or other Android device registered to your Amazon account, click on the above link and look on the right side of the web page. Amazon will tell you if it will work with your registered device.

Have fun!

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