How did New York City get "the big apple" as a nickname?

Question

I read this question somewhere else recently but, never had a chance to read the answer.

Answer 1

From Ask Yahoo!:

Why is New York City nicknamed "The Big Apple"?

According to the Evan Morris, the Web's Word Detective, and author of a syndicated newspaper column specializing in linguistic questions, the trail leads back more than 70 years to a newspaper column called "Around the Big Apple."
Morris cites a noted slang historian who managed to track the phrase to a colorful 1920s horse-racing columnist named John Fitzgerald. Apparently, Fitzgerald heard the term from stable hands in New Orleans who lovingly referred to New York City's racetracks as "...the dream of every lad that ever threw a leg over a thoroughbred. There's only one Big Apple. That's New York." In the 1930s, the term was adopted by jazz musicians, when Harlem was the site of all the choicest gigs.

In 1971 "Big Apple" became the catch phrase of the city's official tourism campaign. Its aim was to improve Manhattan's image as a fun and wholesome place to visit, rather than a dark and dangerous city of crime.

Answer 2

Here is a very good article which gives quite a few reasons.

Answer 3

I found a fairly explicit article about this origin at:

http://www.worldwidewords.org/qa/qa-big5.htm