Next hot trend: Mini smartphones

These days, picking out a smartphone is almost like trying on shoes. Does a four inch, four and a half inch, or five inch screen fit best?

For years, the trend in major smartphone brands' screen sizes had been the bigger, the better. Whether it was the iPhone 5's extra row of apps or the giant, tablet sized Android "phablets," phones had definitely been getting larger.

But recently, that trend has begun to reverse. Samsung and BlackBerry released mini versions of their top-of-the-line smartphones and Apple and HTC are rumored to follow suit. The Samsung Galaxy S4 mini has a 4.3 inch screen, which shaves off more than a half inch off its larger version. The BlackBerry Q5 isn't smaller in size than the top-of-the-line Q10, but it uses all of last year's technology inside.

Larger screens can contribute significantly to the price of a smartphone, so smaller devices released by low-cost smartphone makers like China-based Huawei, ZTE and Lenovo are wildly popular in those regions. The iPhone isn't even in the top five list of best-selling smartphones in China.

As for rumors surrounding Apple and a new, smaller iPhone, it definitely would be an out-of-character move for a company used to marketing exclusively to the high-end of the market. But it has been six years since they entered the smartphone market and there's now more competition.

"They would be smart to come out with two devices, maybe more, and let the customer choose," Kagan said. Even if price trumps screen preference in emerging markets for now, it may not be a tradeoff customers will have to face going forward.

"There is no question display costs are coming down and we expect five-inch devices to be the norm for low-end emerging market adoption in 2014 and beyond," Reith said.