If Apple is indeed planning an iPad mini, it shouldn't make it too small, based on some new research. In fact, it might be a good idea to just keep the iPad the same size and let those who want a smaller screen go for an iPod touch.

As the tablet market continues to heat up, manufacturers are striving to differentiate next-generation products to compete with the iPad, according to Stephanie Ethier, senior analyst, Research and Markets (http://www.researchandmarkets.com). Screen size has emerged not only as a key differentiator, but also the leading indicator of different tablet usages.

New data from the research group highlights top tablet usage scenarios based on device screen size and provides market insight based on the different tablet form factors. For example, tablets with smaller form factors in the 3.5-inch to less than 7-inch range best serve entertainment needs that are typically considered complementary to everyday activities like commuting, exercising, and other on-the-go activities. Recent Research and Markets research findings include:

° Worldwide shipments for tablets with screen sizes between 3.5-7 inches -- more commonly known as portable media players -- will decline throughout the forecast period to 15.6 million in 2016.

° Despite anticipated price erosion, revenue in the 7-inch to less than 8.5-inch form factor represents one of the brightest spots in the tablet market due to anticipated Amazon Kindle Fire demand.

Due to continued iPad success, tablets in the 9.7 to less than 11 form factor category will represent 65% of worldwide tablet shipments.

The bill of materials for a 9.7 tablet will fall to US$246 by 2016 due primarily to strong consumer demand and declining display costs.

-- Dennis Sellers