Just six months after its launch, and little over a month since breaking the 300 million mark, Apple has announced its amazingly successful App Store has already dished up more than 500 million downloads to iPhone and iPod Touch users. According to the company, the store now features some 15,000 applications and has doubled its average download rate to nearly 5 million per day, up from 2.2 million in early December.

This is a remarkable achievement by any stretch, one that has taken even developers by surprise, who increasingly see the platform as a lucrative opportunity. Take Sebastian Trujillo, for example, a developer that wrote a simple yet clever application called "Fake Calls" with the goal of giving people graceful exits from boring situations - users need only to select the contact they want to receive the call from and set up a timer for the call to come in.

Fake Calls is available for 99 cents and has recently surpassed the 50,000 downloads mark, which means that even after Apple takes their 30 percent cut, Trujillo gets a nice sum for an app that took just a couple of weeks to develop. Like him, there are many others who have found commercial success thanks to the iPhone platform.