I find this a game to play if you're extremely bored...
So the 'story' behind this game is that these pigs store these bird's eggs, and pretty much the birds are angry (hence the title), and attack the pigs to get back the eggs (pretty much what a real bird would do to you).
This game pretty much consist of flinging birds on a slingshot into the pigs and blocks. That's it. Every level is just flinging birds into pigs.
Granted you get different birds and levels get harder, but you are still flinging birds...
I have to say the game is kind of funny, and needless to say it's a cute idea in some odd sense.
However, I feel like it's a game that you would play if you are just bored enough.
Like if you're a train trip, waiting for food, or even on a plane.