A forecast by market analysts Informa says Apple’s iPad will dominate the market for tablets until 2015, when devices running Android and other operating systems will finally take over.

The study, summarised on Mashable, says Apple currently holds about 75% of the market. However, total sales are expected to balloon from less than 20 million units in 2010 to over 230 million in 2015, and serious competition is only just arriving on the market.

By 2015, Apple’s share will be around 38%, Informa says, with devices running competing operating systems like Android or webOS making up the rest. Android will take the number one spot the following year.

A competing study published by Gartner in April suggested Apple would hold 47% of the market in 2015, compared with Android devices’ 38%.

Two of the most competitive iPad challengers have just been released in New Zealand – check out our stories on the Motorola Xoom here, and the HP TouchPad here.