Rankings
Are you interested in how your airline is fending compared to the others? If so, click on the "rankings" button at the top. There are 3 types of rankings in AM, "Airline Rankings", "Aircraft Rankings", and "Alliance Rankings".
Airline Rankings
This is the default page of "rankings". Here you can see the ranking of airlines listed according to their value. The airline value is the the net worth of the airline, which is calculated based on cash and the book values of the aircrafts the airline owns. On the same page, you can see the airline code and player's id, which would be useful when dealing with each other.
Clicking on the name of a airline would bring you the details of the airline. The information page includes the fleet, a list of gates, a route map, and some statistics (daily passenger, longest route, most fuel use) of the airline. From there, you could click on the airport codes to view the detail of the airports the airline is operating in.
Aircraft Rankings
Aircraft Rankings is the second selection for the rankings page. In this page, you can see the type os aircrafts airlines are operating. The types of aircraft are listed by the number in service. This ranking is a good reference as to which type of aircraft is profitable (assuming that other players are smart and the more popular a type is, the more profitable it is).
Clicking on a type of aircraft would bring you to the list of airlines that own it. The quantity owned by the airlines is also listed.
Alliance Rankings
This is the third selection in the rankings page. You can check the ranking of your alliance here. They are listed by total net worth in descending order.