Barclays issued issued a report today suggesting that phablets -- generally described as phones measuring more than 5 inches diagonally -- could hit 402 million sales by 2015. That's an extremely notable prediction, because the total smartphone market should total about 700 million this year, and perhaps a billion by 2015. Barclays believes 84 million phablets were shipped last year, as a comparison.

While definitions of a phablet vary, the implication is that phones are getting larger. That could be bad news for Apple (AAPL 0.53%). Though the company controls 18% of smartphones globally as of 2012, key geographic areas such as the United States see much higher market share. For example, on AT&T (T 0.12%), Apple's share exceeds 70% of smartphone activations in some quarters. When you have such high market share, even if a non-majority of smartphone users prefer larger screens, those niches can quickly start chipping away at market share.

So far Apple has resisted a larger iPhone screen, deciding on a 4-inch screen with the iPhone 5. In the following video, Fool tech analyst Eric Bleeker notes that with large screens continuing to gain traction in the Android space, it only seems like a matter of time before Apple introduces a larger iPhone to compliment the one with a smaller screen. After all, in spite of all the fretting over Apple's unwillingness to compromise on a smaller iPad, we now see the success and rave reviews the iPad Mini has commanded in its short time on the market. To see Eric's full thoughts, make sure to watch the video.