Each achievement has its own value. For example, if you have flown 5 different Airbus planes, you will achieve "Airbus". Below you will find some screenshots on how to check your achievements.
In addition, there are different types of levels. As you can see, there are numbers under the icons. For example, planes with 3 numbers mean that you are at level 3 (every 5 different planes - you go to a new level).
Go to your profile → Click on "Achievements".
There are three types of achievements – countries (for countries visited), special (for flights), and events (for attending special App in the Air events).
There are three types of achievements - countries (for countries visited), special (for flights) and events (for attending special App in the Air events).
When you tap on the achievement, you will see the definition of it.