What is Apple cooking up for a large iPad-like device?

Is Apple going to take a crack at a hybrid? Or is it eying a more conventional product?

Those are burning questions that analysts and the supply chain are trying to figure out.

Predicting Apple's next move has become a sport. With the supply chain (in the case of Apple, largely the collection of component suppliers) the arena where, after some trial-and-error, a final product emerges the winner.

Market researchers are the bookies, calculating the odds based on their best educated guess from supply chain sources.

The iPhone 6 is the latest example: the odds seem to favor a 4.8-inch (roughly) phone and, possibly later, a larger phone-like device.

But analysts are stumped -- at the moment -- as to what the 13-inch (or 12.85-inch, depending on who you talk to) "iPad Pro" is exactly.

One source with connections in the Asian supply chain told me this week that there is an "internal debate" at the source's company as to whether it's "targeted for the notebook line, rather than the iPad line."

"Provided it's actually in development rather than in testing," the source added.

But here's a real product that may give impetus for Apple to bring out a larger iPad-esque device: the 12.2-inch (large by tablet standards) Galaxy Tab Pro, which Samsung has just begun selling.

The South Korean company is marketing it as a business-friendly tablet, with a Samsung-branded keyboard and mouse to go with it. If Samsung makes headway with this in markets untapped by the iPad, that could give Apple reason enough.

And the Windows 8/8.1 camp is already making a play for businesses with detachables. The HP Spectre XT is a 13.3-inch Windows 8.1 tablet that plugs into a battery-powered HP keyboard to become a full-fledged laptop.

Lenovo has the 11.6-inch Miix 2, also a tablet that can covert to a laptop.

Apple could of course decide it doesn't need to go there. Speculation suggests that Apple may also be eying a more conventional 12-inch MacBook (maybe an Air).

But I'm betting it does.

HP Spectre 13 detachable: The Windows 8.1 camp is trying to sell hybrids to business customers who want one device that can serve as a tablet and laptop.