The art is very cute and looks pretty polished. The walking animation looks good for the one direction that the animal is always facing. I would say you could get away with mirroring the side view, but you should also consider using a graphic for when the animal is moving up or down. It is a little strange that there are extra animations for animals when they are idle, (the bear stands on a ball when he gets bored), but there are no animations for changing the direction the animal is facing. It is kind of like putting a chandelier inside of a shanty, it is a nice little decoration... there are probably more important things that should have taken priority. Aside from the walking animations this game looks very graphically polished.
The music was very catchy and pretty enjoyable. It may have been my favorite part! Awesome job!
The Gameplay: Was super easy. I think I got a perfect score on every level up until I reached the forest level with the bears. I reset a few puzzles, but also by the time I got to this point in the game I just stopped caring about the score and used as many moves as I wanted. I only played using as many moves as I wanted for about 3 levels before I just stopped caring. I think there needs to be a few things to make this gameplay a little more fun.
-Where is the danger? There is nothing preventing a player from using as many turns as they like to pass a level. Consider your intended audience, if it is young children then I think it is ok to have no penalty for this. But if you are interested in targeting puzzle gamers you should think of a way that the player can ruin lose the level. Maybe set a "par" for each level and if the player cannot pass under par they need to replay it. Maybe create some levels that have holes or someway that if a player does the puzzle wrong they will get stuck or blocked from moving at all.
-Increase complexity faster. I think you can probably cut out the most of the Antarctica levels. Try to measure when these puzzles actually get interesting. This is basically the hardest thing to do. Come up with good puzzles that are going to be hard enough to be fun, but also easy enough to keep people playing and not get frustrated.
-This game kind of reminds me of Chocolate Castle, you might want to consider give that a play through and see how they structure some of their puzzles. http://www.lexaloffle.com/choc.php
The mechanic in chocolate castle is slightly different since you are just eating chocolate and not potentially flipping floor tiles. But it does have cooperative puzzles similar to yours.
Once I got to the harder levels the game became much more enjoyable. I would say more, but I am at work and should probably get back to it.