Rovio has Angry Birds for Windows Phone 7 or Windows Phone 8 in the Windows Phone Store for FREE for a limited time. Deal expires May 15, 2013.

Use the unique powers of the Angry Birds to destroy the greedy pigs’ defenses!

The survival of the Angry Birds is at stake. Dish out revenge on the greedy pigs who stole their eggs. Use the unique powers of each bird to destroy the pigs’ defenses. Angry Birds features challenging physics-based gameplay and hours of replay value. Each of the over 300 levels require logic, skill, and brute force to crush the enemy.