- 1). Tap on the "Marketplace" icon, which is in the Start menu of your phone.
- 2). Touch "Apps" and tap on the search button. Type "Angry Birds" in the search box and click on the game's name in the list of results.
- 3). Push the "Buy" icon and select the payment method you want to use. You can either pay for the application by using a credit card or by letting Microsoft add a charge to your phone bill.
- 4). Tap on "Buy" again to confirm your purchase. Your phone will now automatically download and install the game. You will be able to launch it from your phone's Start menu.
Source...