Great game! It looks very polished and plays very well. The art, the animation, the sounds are all very cohesive and feel like a very professional pack.
Maybe a monkey thowing barrels lacks some creativity, but it makes the gameplay very clear and easy to understand. What I find hard is, that I feel very much out of control. You can spam left and right and things happen, but I am not able to find a strategy and if some zookeepers are on the ladders if a barrel rolls by, this is often times enough to end my run.
All in all, a very good entry!