Full list of all 20 Angry Birds Stella achievements worth 200 gamerscore. It takes around 15-20 hours to unlock all of the achievements on Windows Phone.
200 bounces with Stella
Completed Episode 1
Played Game for One Hour
Popped 1,000 Pigs
Used the Hammer Power-up ten times
Earned 100 Stars
Earned 50 Stars
Get one bird to bounce on 5 drums in one level
Used the Hammer Power-up
Found 1 Photograph
Earn 200 Stars
Earn 300 Stars
Earn 5,000 Coins
Spend 5,000 Coins
Complete Episode 2
Find 30 Photographs
50 Three Starred Levels
131 Three Starred Levels
1,000 bounces with Stella
Play Game for Ten Hours