Apple's app store continues to rage forward, attracting new developers at a steady rate. Around 35,000 unique companies across the globe are producing the 140,000-strong collection of applications that can be found in the App Store. But where did all these application designers come from?

A new study conducted by mobile research analytics company Flurry suggests iPhone developers were attracted to the platform from a range of different backgrounds.

Some developers transposed their content creation skills from rival gaming or internet platforms to the iPhone platform to create their popular applications. Others made their first leap into the world of application development via the App Store - attracted by the lure of cold hard cash.

According to the study, 20 percent of iPhone applications were made by companies that started out on the web. Another 19 percent of applications were made by traditional gaming companies such as Electronic Arts and Activision.

Brick-and-mortar companies have produced around 19 percent of the iPhone applications to date while traditional media companies like Disney, New York Times and CBS are responsible for another 17 percent of the applications.

Five percent of application developers started out on a different mobile platform before developing for Apple.

But the most positive news to come out of the study is the number of smaller start-ups that were founded to create native applications for the iPhone platform.

"Despite the fact that the App Store is now maturing, reaching its two year anniversary this summer, we are encouraged that native iPhone application developers are still relevant, representing 20% of the heritage pie, the second largest category. This means that the barrier to entry is still low enough for start-ups to enter and innovation to flourish," wrote Flurry's VP Marketing, Peter Farago on March 15.

The study also found that the impending release of the iPad was generating a huge surge in new iPhone OS projects. Since the iPad was announced on January 27 the number of new iPhone OS applications has increased by 185 percent.

Flurry's list of iPhone Developer DNA:
1. Native iPhone: Companies founded to create applications for iPhone (e.g., Freeverse, PageOnce)
2. Traditional Media: Companies established on Film, TV, Print and Radio (e.g., Disney, TBS, NYT)
3. Mobile: Companies having started on J2ME, BREW, BlackBerry, etc. (e.g., Digital Chocolate, eBuddy)
4. Retail & CPG: Brick-and-mortar companies or ones that manufacture goods (e.g., The Gap, DKNY, Kraft)
5. Online: Companies who began on the web including e-Commerce, social networks, online gaming, streaming music, etc. (e.g., Google, eBay, Facebook, Pandora, PopCap, Zynga)
6. Traditional Gaming: Video game companies from console, portable or PC (e.g., EA, Activision).

The full study can be viewed here: