Here is the full list of all 50 Fly Corp achievements.
The base game contains 42 achievements, and there is 1 DLC pack containing 8 achievements.
Collect all postage stamps in Europe
Collect all postage stamps in Asia
Collect all postage stamps in North America
Collect all postage stamps in South America
Collect all postage stamps in Africa
Collect all postage stamps in Australia and Oceania
Complete one level in Ladder Mode
Complete ten levels in Ladder Mode