Apple unveiled a smaller version of its hot-selling iPad on Tuesday, jumping into the market for smaller tablet computers dominated by Amazon, Google, and Samsung.

"This is iPad mini," Apple's senior vice president for marketing Phil Schiller said as he displayed the new iPad at an Apple event in San Jose.

"This isn't just a shrunken down iPad," Schiller said. "It is an entirely new design."

The iPad mini's touchscreen measures 7.9 inches diagonally compared to 9.7 inches on the original iPad.

According to the Apple Singapore website, the new iPad mini will retail in Singapore from S$448.

Schiller said customers could begin pre-ordering the iPad mini on October 26 and Wi-Fi versions would begin shipping on November 2 to about three dozen countries in Asia and Europe in addition to the United States.

Schiller said the iPad mini weighs 0.68 pounds, is just 7.2mm thick — thinner than a pencil — and comes in both black and white models.

Apple also unveiled a fourth generation of the original iPad on Tuesday for a 16GB model with Wi-Fi connectivity.

The event comes three days ahead of the release of Microsoft's new Windows-powered Surface tablet and two days before Apple reports quarterly earnings.

Microsoft's Surface has a 10.6-inch screen and starts at $499, challenging the larger-format iPads.