Airport Codes (IATA) Free

This app contains an offline database for the IATA codes of thousands of airports, airlines and aircraft types.
An IATA airport code is a three-letter code designating many airports around the world, defined by the International Air Transport Association (IATA). The characters prominently displayed on baggage tags attached at airport check-in desks are an example of a way these codes are used.
IATA also provides codes for railway stations and for airport handling entities. A list of airports sorted by IATA code is available. A list of railway station codes, shared in agreements between airlines and rail lines such as Amtrak, SNCF French Rail, and Deutsche Bahn, is available. There is also a separate list of Amtrak station codes, three-character codes used by Amtrak for its railway stations in the United States and Canada.