This year's iPhone could see one of the biggest changes yet for Apple's smartphone line, says one analyst.
Last month, Apple unveiled a new type of trackpad for its updatedand its . Dubbed , the new trackpad is pressure-sensitive, so it responds to how you press on the surface.
The Apple Watch, which goes on sale this month, also is equipped with Force Touch.
That, according to the Wall Street Journal and others, including KGI Securities analyst Ming-Chi Kuo.
In an investors note released Thursday and picked up by AppleInsider, Kuo said that Force Touch will be "the most significant change" to the iPhone's interface to date -- so significant that Apple could even dub this year's model the iPhone 7 rather than the iPhone 6S.
The iPhone line is hugely important to Apple. It is theof the company's revenue, and its financial importance was made vividly clear in the final quarter of calendar 2014 when record sales of 74.5 million iPhones for quarterly profits ($18 billion) among publicly traded companies. (By contrast, sales of the iPad continued to slump.)
In an intensely competitive smartphone market, Apple also needs to keep advancing the technology in the iPhone to keep consumers from being tempted by rivals. Samsung, for one, continues to step up its game -- its new Galaxy 6 shifted to a more high-end metal body from the traditional plastic, along with adding other improvements, and the Galaxy 6 Edge features an eye-catching display that wraps around the edge of the phone.
With the iPhone 6 and iPhone 6 Plus, introduced last September, Apple made a belated nod toward the field of "phablets," or jumbo smartphones, that had been established in large part by Samsung models. Those latest iPhones also introduced the Apple Pay mobile payments technology.
Apple typically launches a major new iPhone model every other year, with lesser upgrades in the interim years. The practice has become so common that analysts and users alike have come to expect only small improvements and a few new features for the so-called S models, such as last year's iPhone 5S. But the addition of Force Touch would indeed alter the way the entire touch interface is used -- not only resulting in a major upgrade but also giving the iPhone a competitive edge over rival phones.
Instead of simply detecting the pressure of a touch, the iPhone's Force Touch might work a bit differently, according to Kuo.
"We believe that iPhone's Force Touch sensor doesn't directly detect the pressure applied by fingers," Kuo said. "Instead, it monitors the contact area on which the finger touches the screen to decide how big the pressure is."
The analyst said he believes Force Touch on the iPhone will use capacitive technology, which responds to the electrical conductive properties of your finger, thus allowing for a lighter touch. The Force Touch sensor itself would be placed under the phone's in-cell touch panel's backlight. An in-cell touch panel combines the phone's touch sensors directly with the LCD screen into a single layer, which would space in the tight quarters of a smartphone.
Kuo also said he expects this year's iPhones to stick with the same screen sizes of 4.7 inches and 5.5 inches, introduced with the iPhone 6 and iPhone 6 Plus, respectively. Some rumors have suggested that Apple would unveil a 4-inch model for consumers who don't like the bigger-screen phones.
Kuo doesn't see a new 4-inch phone in his crystal ball but said that the iPhone 5S, which has a 4-inch display, could be reintroduced with a plastic back. That would create a low-cost, entry-level iPhone for budget-conscious consumers who prefer a smaller phone.
A spokeswoman for Apple declined CNET's request for comment.