Apple said its iPad Pro will be available to order online on Wednesday and arrive at stores later this week.
The 12.9 inch-screen tablet, which starts at $799 but costs more than $1,000 if buyers also want a keyboard and an optional stylus, will be available in more than 40 countries, including the United States, the UK, China and Japan.
Sales of iPads have been falling for several quarters as big-screen iPhones appeal to more consumers.
Apple sold 54.86 million iPads in the year ended Sept. 26 -- a drop of 19 percent from a year earlier.
Since launching iPad with a 9.7-inch screen in 2010, Apple has released a mini version in 2012 with a 7.9-inch screen.
Apple unveiled the larger iPad Pro on Sept. 9, hoping to rival Microsoft Corp's 12-inch Surface Pro 3 in attracting business customers.
Research firm Forrester projects that sales to businesses will represent as much as 20 percent of the overall tablet market by 2018, compared to 14 percent this year, as the market grows from 218 million units to 250 million units.
Ahead of the launch, Apple touted the new iPad in a video ad titled "A Great Big Universe":