Coming on Wednesday to New York?

The announcement of a press conference by the internet retailer on 28 September has primed expectation of a serious rival to Apple's iPad

Amazon has sent out invitations to a press conference in New York straightway Wednesday at which it is expected to unveil a tablet based on Google's Android operating system. Analysts say that the offering, from the company which revolutionised electronic reading with its Kindle e-reader, could provide the first serious challenge to Apple's iPad.

The company declined to comment on what will be released nevertheless analysts were confident that the world's largest Internet retailer will use the tablet computer to expand in mobile commerce and sell more digital goods and services.

The tablet have leaked out via suppliers

Some details of the tablet have leaked out via suppliers and the press: it is expected to have a 7in touch screen and run Amazon's own version of Android. During there are many Android tablets on sale, none has been able to compete effectively with Apple's iPad, of which about 29m have been sold since its launch in April 2010. A report on Techcrunch previously this month recommended that it will as well be called Kindle.

"It's a marketing tool to build a relationship with clients and sell them cloud services," said James McQuivey, an analyst with Forrester Technology.

Earlier this week Amazon made its own Android software store available internationally, a necessary precursor to the launch of its tablet as it would allow people to download apps and e-books for it directly. Amazon is expected to run its own "app store" separately of the one run by Google, and to maintain its own content purchasing system.

The tablet could pose a major threat to Apple because of the Kindle's popularity and the movie and music services Amazon sells.

Several research companies like Innovation In Motion and Samsung have introduced tablets that have sold poorly. Hewlett Packard Co announced in August it would abandon its TouchPad tablet.

Survey suggests Apple's iPad has near three-quarters of market as up to 2 million more prepare to buy tablets in at once year. By Charles Arthur