Absolutely worthless. You win for the first 40 or so levels, the game even helps you out, but after that, you literally cannot win without paying money. They levels are randomly generated and you cant swap between more than 3 birds and the ideal bird for your situation is ALWAYS inaccesible when you need it. I have spoken to several friends who have all noticed the same thing, the game has become a cash grab and isnt worth the time to download. There are far better games to play out there.