Apple's (AAPL 0.56%) next flagship iPhone, the iPhone 6, is widely expected to have a 4.7-inch screen. Several major media outlets, including The Wall Street Journal, Bloomberg, and the Nikkei have reported on the existence of a forthcoming larger iPhone, too.

But by the time the 4.7-inch iPhone 6 is released, will it be too small? Ahead of the iPhone 6's debut, Android hardware manufacturers have continued to offer larger phones, many of which would dwarf a 4.7-inch iPhone.

LG, Samsung and HTC's phones just keep getting bigger
HTC was one of the first handset manufacturers to offer a larger smartphone -- its EVO 4G, released in 2010, sported a 4.3-inch screen that reviews (at the time) characterized as "beastly." In retrospect, it was positively tiny, as HTC's current flagship, the One M8, is nearly an inch larger.

Samsung (NASDAQOTH: SSNLF), too, has gone bigger over time. The original Galaxy S was only 4 inches; the Galaxy S5 is 5.1. That means that Samsung's current flagship is almost as large as its original phablet, the 5.3-inch Galaxy Note.

LG's 2014 flagship, the G3, actually is larger. At 5.5-inches, it's the same size as LG's prior phablets. With the G lineup converging with its Optimus phones, LG may be poised to phase out smaller smartphones entirely, focusing strictly on phablets, and calling into question the need to even make such a distinction.

Will Apple release a phablet?
Many of the reports that have said Apple is planning to release a 4.7-inch iPhone have also claimed that it will release a 5.5-inch variant -- its own phablet; an alternative to Samsung's Galaxy Note.

But the likelyhood of this phone releasing in the near future is far from certain. Reuters, citing supply chain sources, reported that Apple had run into issues with the 5.5-inch screen, and was forced to delay its production by several months. Taiwanese website Commercial Times went further, claiming that 5.5-inch iPhone would not be released until 2015.

Of course, these reports are unconfirmed and unreliable. What's far more certain is the growing popularity of phablets, and the glaring lack of a such a device in Apple's product portfolio.

Samsung said it sold more than 10 million Galaxy Note IIIs during the device's first two months on the market, and that emerging markets in particular have been highly receptive. Research firm IDC made a similar observation, noting that phablets outsold both and tablets and laptops in most Asian countries during the second quarter of last year. On a global basis, analysts at Deloitte Canada now expect phablets to outsell tablets in 2014.

Apple is aware of its size problem
Despite not releasing a larger smartphone, Apple is well aware of the demand. In an internal slide originally composed in 2012, Apple declared that consumers wanted what it didn't have -- namely larger phones with screen sizes larger than 4 inches.

But that slide seems woefully out of date. With most Android manufacturers having moved on to phones even larger, a better dividing line may have been 5-inches, or perhaps even more. Assuming it's released, a 4.7-inch iPhone would be a step in the right direction, but with the market shifting toward phablets, even that may be far too small. More important to the future of Apple's handset business could be its 5.5-inch phablet -- hopefully the company debuts such a device later this year.