Rumors of the 5.5-inch-class "iPhone 6" -- or whatever Apple would choose to call it -- are getting more intriguing by the week. A widely cited report from Taiwan's United Daily News/Economic Daily on Friday said that out of the 80 million iPhone 6 units that the supply chain of component manufacturers expects Apple to sell this year, more than 90 percent of the shipments will be for the 4.7-inch model. (That part of the original Chinese-language story was not widely reported.) That leaves a small percentage, possibly less than 10 percent, for the 5.5-inch phablet-size device. If accurate, why such relatively small numbers? One of the most often cited reasons is the high cost and/or lack of availability of sapphire as a display cover material. That coveted material has been used very sparingly -- as a cover for the fingerprint scanner, for example -- in the iPhone 5S. One of the sources for this speculation was an April research note from KGI Securities analyst Ming Chi-Kuo, who said that, because of supply constraints, only high-end iPhones, like the priciest versions of the 5.5-incher, may include a sapphire screen. KGI also expects the 5.5-inch phone to see shipments come in below 10 million units in 2014. Then there's the reported battery manufacturing issues that are tied to the rumored extreme thinness of the phone and the resulting need for an unusually thin battery. Finally, there's the 1,920x1,080 (401 pixels per inch) display that's expected for the 5.5-incher. That would be the highest pixel density for an Apple Retina device to date and may be a challenge to manufacture in the extra-large volumes Apple requires for mainstream devices. (For the record, that would be below the 432 pixels per inch of the Samsung Galaxy S5's AMOLED 5.1-inch display.) Of course, we don't know how accurate the supply-constraint and specification rumors are at this point, but one thing seems pretty certain: if Apple is going ahead with the 5.5-inch phone, it will likely be at the apex of Apple's mobile products and priced accordingly. And that means it would be packed with the best technology Apple can muster. Let's just hope Apple actually makes the thing and it gets to market before the end of the year.
