Nokia officially entered the mobile applications market on Tuesday after opening its online software and content store, Ovi Store.

The portal will host a variety of applications to around 50 million customers worldwide so far and users in Australia, Germany, Ireland, Italy, Russia, Singapore, Spain and the United Kingdom will be able to purchase immediately and get billed by their network operator.

The Ovi store is accessible via a downloaded application and users will have to create a profile at the Ovi web site to use the service.

Nokia aims to follow the success of Apple's App Store with its new offering. Apple's store has proved extremely popular, with one billion applications downloaded in less than a year, and operators and technology firms including Vodafone Nokia, and Microsoft now also want to get in on the action.

The Finnish handset maker began rolling out the store on Monday, opening it to a few users of its phone models in Australia and Singapore.

Nokia said clients in eight countries can pay for purchases through their phone bills, and AT&T was planning to make the store available to its clients in the United States later in 2009.

AT&T looks forward to introducing Ovi Store for our customers later this year, said David Christopher, chief marketing officer of AT&T Mobility and Consumer Markets.