Few high-profile design changes: Having come up with an all-new aesthetic for the iPhone 6, Apple is unlikely to alter the overall look and feel of the handset for the next update. Until recently, the assumption was that the iPhone 6S or iPhone 7 would look all but identical to its predecessor, but the latest reports suggest that the new phone may be slightly thicker, taller and wider (see above). Most analysts still believe that there will be no dramatic redesign, with most physical changes imperceptible at first glance.
New aluminium frame: Although the design is unlikely to change substantially, it may be built from a new material. According to Taiwan's Economic Daily News, Apple is planning to make use of the "Series 7000" aluminium alloy it developed for the Apple Watch on its smartphones too. The metal is "designed to be 60 per cent stronger than most aluminum, and one-third the density of stainless steel, while still maintaining a light weight", MacRumors says.
Force Touch: The Apple Watch introduced a feature called Force Touch, enabling it to differentiate between a light touch and a firmer tap on its screen. The system, intended to speed up and refine touchscreen controls within the watch's space constraints, is now likely to be rolled out across Apple's smartphone rangetoo, as well as its MacBook laptop trackpads.
Higher-resolution screen: When Apple launched the iPhone 4 in June 2010, it said the "Retina" screen provided the maximum resolution perceptible to the human eye. Nevertheless, it stepped up resolution for the iPhone 6 Plus, boosting pixels per inch from 326 to 401 for its supersized smartphone and describing the new screen as a "Retina HD Display". The 4.7-inch model retained the 326ppi screen, but reports from China quoting supply chain sources suggest that the smaller version of the iPhone 7 may get a screen that's slightly larger and significantly sharper. "The iPhone 7 could very well sport a five-inch screen with 400ppi resolution," says IT Pro. Changing the size of the screen would be an unusual step for the first upgrade following a major redesign, but it would tally with the claim that the frame of the new handset will also be slightly larger than the one it replaces.
Samsung chips: It may be all change under the skin too, if reports that Samsung will be making the iPhone 6S or 7 processors proves correct. Bloomberg quotes "people with direct knowledge of the matter" who say that Samsung has regained its monopoly on Apple's chip business. Last year it lost part of the contract to Taiwan Semiconductor Manufacturing Co.
Dual-lens camera: In February rumours emerged that the camera could be in line for a substantial overhaul. John Gruber of Daring Fireball, a respected source of Apple information, said he has heard that the iPhone 7 might get "the biggest camera jump ever". He added: "I don't even know what sense this makes, but I've heard that it's some kind of weird two-lens system where the back camera uses two lenses and it somehow takes it up into DSLR quality imagery." That vague suggestion has now been largely discredited, as adding a second lens to the rear of the camera would require a thorough redesign of the handset chassis, and that's unlikely so soon after the all-new iPhone 6 was released. Nevertheless, much speculation has been devoted to the camera, and changes are still expected.
3-D camera: Another long-shot, but not entirely out of the question. Apple has recently snapped up an Israeli-based company called LinX, which specialises in high-tech camera sensors. That, according to Business Insider, could have a dramatic effect on the camera capability of the iPhone 7. "LinX's technology won't only enable the iPhone to take better, sharper images – it could also allow the phone to capture three-dimensional photos, eliminate an annoying aesthetic problem where the cameras on the latest iPhones stick out, and solve a bunch of other problems." Having spent $20m acquiring the company, Apple is likely to be looking for ways to capitalise on the technology it now owns – but it may not be ready in time for the iPhone 7.
The demise of the iPhone 5C: When Apple introduced the multi-coloured iPhone 5C in 2014, it was seen as a bit to broaden the appeal of the phone beyond the premium market. However, sales figures for the 5C have been disappointing, while the high-end iPhone 6 and 6 Plus have been runaway successes. It therefore seems likely that Apple will kill off its sub-prime plastic handset - but keep on the aluminium-framed iPhone 5S to cater for customers who still want a four-inch smartphone.