It works well for for American, which is more than I can say for Americans app. It also found my flight on Hawaiian which is booked next year.
In addition to the seat map it also provides some information about the aircraft and lets you know about different versions of the aircraft the airlines uses. For example, it let me know that American flies 5 different versions of the 757-200 and can display a map of each. Unfortunately, its not smart enough to know what exact aircraft the flight will use.
It also provides photos of the aircraft, but most shots are very amateur.
One useful thing I found about this app is it is good for quickly comparing the seat recline pitches. For example, its easy to see with this app that some airlines business seat pitch is not much better than other airlines economy seating.
In summary, totally recommend.
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