Ever since Apple opened its Apps Store on iTunes to outside developers in July 2008, there are more than 140,000 different iPhone apps that have appeared. Thanks to Apple, the app market is already worth nearly two and a half billion dollars a year, according to AdMob, an advertising company.

Most current apps that are available are made by independent developers and are mostly intended to entertain. They have not required much work to be developed. However, the novelty of these apps has ensured that many developers have made profits on them, creating a new kind of entrepreneur called "app developer".

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