Without question, the iPhone 6 on release date will be a big hit, outselling its Android rivals and its predecessor, the iPhone 5S, even when not sporting a supersized display panel or simply sticking to a 4-inch screen.

Galen Gruman of InfoWorld is not too sold on the idea that Apple needs to dance with the so-called phablet craze that Samsung has started with the first Galaxy Note in 2011. Gruman, according to BGR, called the oversized smartphones as part of a niche market, which suggests that phablet or not phablet the next iPhone remains a force to reckon with.

Looking deeper, the analyst noted that among the phablets that came out in 2013, it's only the Galaxy Note 3 that has registered respectable sales figures, likely clocking around 11 million unit sales as of December 2013.

Other players remain grappling on how to deal with the Galaxy Note phenomenon as Gruman told BGR that "even in the Android world, the big-screen smartphone is not the red-hot seller you might think."

But one handset proved as the runaway winner - the iPhone 5S, which Gruman said collected some 32 million sales in Q4 2013 and the numbers could have been greater had Apple only delivered sufficient supplies during the holiday quarter last year.

Apple's 2013 flagship completely outpaced the Galaxy S4, which in the last three months of the same year cleared 20 million units. So Gruman expects the iPhone 6 to replicate or even surpass the iPhone 5S even if the former would keep the 4-inch screen that Apple insists is the optimal standard for mobile phones.

And this early, the spectre of a hot-selling iPhone 6 is virtually certain, according to a report by R.W. Baird analyst William Power, which was first published in Barron's.

More than 17 per cent of U.S. consumers are likely to buy the upgraded iPhone following its release date this year compared to the 5.3 per cent surveyed last year, who declared intents of taking home the iPhone 5S.

The data was based on the research result conducted on 1000 respondents around the United States, attempting to measure the likely reception that the iPhone 6 would generate following its much-awaited debut.

The R.W. Baird report also indicated that more than three out of 10 of those queried are current iPhone owners, who have been using iPhone 5S and 5C in the last five months.

"Notably, 5S and 5C owners ... were the most likely to say that they definitely plan to purchase the iPhone 6, suggesting an ongoing upgrade opportunity," Power told Barron's.

On this note, it is likely that the iPhone 6 will lure some 45 million of minimum initial buyers once it becomes available, basing on the data offered by Gruman in his report.

And the same numbers, according to Power, could easily shoot up should Apple decide to stretch the iPhone 6 screen size. He added that by opting for a larger/wider display in the next iPhone, the tech giant is poised to gain traction in Asia, where the phablet form-factor is immensely popular.

However, having a screen that is bigger than its current standard remains a big question mark for the iPhone 6 as reports suggest that Apple CEO Tim Cook is still searching for the reliable display technology that will convince him to ditch the 4-inch iPhone 5S screen and go phablet for the next iteration.

In the absence of solid proof or confirmation from Apple, the iPhone 6 on release date will likely keep the 4-inch screen profile while introducing innovative features such as Liquidmetal casing, sapphire glass and coating, 64-bit A8 processing chip and iOS 8.