Apple users have downloaded more than 60 million programs from the App Store since its launch a month ago, according to CEO Steve Jobs.

While most of the programs are free, Jobs told The Wall Street Journal that Apple sold an average of $1 million worth of applications a day. If these figures hold up, it could lead to $360 million a year in new revenue.

"This thing's going to crest a half a billion soon," Jobs said. "Who knows, maybe it will be a $1 billion marketplace at some point in time."

Apple won't get all that money, as application developers keep 70% of sales. Jobs said developers earned about $21 million in the first month. While Apple gets 30% of all sales, the company's CEO said the real value is increasing the appeal of devices like the iPhone, iPhone 3G, and iPod Touch.

"Phone differentiation used to be about radios and antennas and things like that," said Jobs. "We think, going forward, the phone of the future will be differentiated by software."

Video games have been one of the most popular application categories, as the iPhone offers game developers an attractive mobile platform because of its robust processor, motion controls, a touch screen, and strong graphics capabilities. Sega said it has sold more than 300,000 copies of its Super Monkey Ball game at $9.99 a piece.

Enterprise apps from companies like Oracle haven't been as popular, but that may change as more iPhone handsets enter corporate markets. Research firm Gartner recently said the iPhone meets the minimum requirements for use on corporate networks, although there are some caveats.

The success of the App Store may be bad news for companies like Microsoft, Nokia, and Google, as they battle to attract quality application developers for their respective mobile platforms.