The current iPhone is barely three months old, but the rumors and reports about what we can expect from its replacement -- which won't be unveiled until September 2015 -- have already begun in earnest and are pointing to an iPhone 6S with a smaller screen.

According to Timothy Arcuri, an analyst with Cowen and Company, Apple is considering offering a ‘mini' version of its next flagship handset with a smaller, 4-inch display.

The mini trend, started by Samsung back in 2012 and followed by LG, HTC and Sony, takes a smaller handset and imbues it with the same look and feel as the full-size flagship but with mid-range processor and display specifications.

In a note to investors, seen by Apple Insider, Arcuri says that his sources suggest the new handset would offer similar performance levels to the iPhone 5S but with the same curved screen edges featured on the iPhone 6 and would be marketed as a replacement for the colorful entry-level iPhone 5C.

Separate reports emanating from Taiwan and China claim that the iPhone 5C's days are already numbered and that Apple will be ceasing its production in early 2015.

Regardless of whether Apple launches a 4-inch headset alongside new 4.7-inch and 5.5-inch models next September, the feature that most consumers want to see is not more or less screen size, but more storage.

Apple is still the only major smartphone maker that doesn't support memory expansion via an SD or Micro SD card, meaning that iPhone owners have to either look to the cloud or pay a huge premium in order to get more space for photos, videos, music and other files.

A survey of UK iPhone owners by app developers I Love Ice Cream published on December 15 found that 8% of respondents ran out of space on their handsets every single day and 12 per cent said that they were forced to delete files to free up space "at least one a week" while 22 per cent experienced the problem once a month.

The study also found that 91 per cent of those polled had opted for the 16GB version of their handset because the bigger 32GB, 64GB or 128GB versions were too expensive.

However, according to Apple analyst Neil Cybart, the company counts on iPhone users running out of space on their 16GB handsets so that when they next get the chance to upgrade, they buy a more expensive version of the handset with more storage.