It seems like everything Apple touches is poised to turn into a profitable business. After the successful iPod + iTunes combo, Apple seems ready to repeat history with its iPhone + AppStore duo.

In just five months since its official release, AppStore has managed to sell over 300 million downloads, as the Cupertino-based company announced on Friday.

In case you are not an iPhone fan, you should know that AppStore is a website that offers downloadable programs for iPhone and iPod Touch. The website went live in July and in just one month sold 60 million programs according to the figures released by Steve Jobs in an August interview with The Wall Street Journal. Ten million applications were sold in the opening weekend.

Apple allows third party developers to post their applications to the App Store after they have been vetted for reliability by Apple technicians. Developers can charge up to $1,000 per download, with 30 per cent of the fee going to Apple.

Apple also noted that currently there are almost 10,000 applications available in the AppStore, which is quite an impressive number, judging by the fact that the store started with 500 applications in July.

As you might imagine the most downloaded applications fold into two categories: games and entertainment. But it is expected that the enterprise applications will soon become favorites due to the release of the 3G iPhone.

Earlier this year, Steve Jobs explained that AppStore is the feature that could differentiate the iPhone from the similar cell phones offered by rivals like Google, Samsung and Nokia.

But Apple’s rivals paid attention to the development of AppStore and they have started to put together similar platforms. For example, Google has Android Market, a store with applications for its mobile platform. Unlike AppStore, Android Market has a less-restrictive approach to the applications sold through this system.

Also, RIM announced that it will release, as soon as early 2009, a similar store for BlackBerry, from where the third party developers will get 80 percent from the prices of their applications.

In the past months, AppStore has made headlines due to the controversy ignited by Apple’s NDA.

After numerous protests from the developer community, Apple decided to drop its NDA attached to the applications that were already released to the AppStore. Apple explained that the NDA was intended to be “just another layer of protection”, so “others don’t steal” Apple’s inventions and innovations that are included in the iPhone and its software.

Acknowledging that the NDA has stirred up a passionate debate amongst the developers, Apple said that: “…we are dropping it for released software”.