San Francisco, Nov 22 (IANS): Apple's upcoming next-generation smartphone iPhone 15 is likely to feature a titanium chassis with curved rear edges, which will replace the existing squared off design.

The back edges of the iPhone 15 are expected to be rounded to create a new border, similar to the bottom edges on the cases of tech giant's 14-inch and 16-inch MacBook Pro models, reports MacRumors.

The iPhone 15 is rumoured to "still have a rear glass", despite the switch to titanium.

If the most recent rumours are true, then the company would be using titanium in iPhones and iPads for the first time, the report said.

Earlier, it was reported that iPhone 15 series would include four models, with bigger feature differences than the iPhone 14 and all the models would feature USB-C charging port.

The tech giant would produce four models for its 2023 iPhone 15 range.

While, another report mentioned that iPhone 15 Pro models are likely to feature a Thunderbolt port for high-speed data transfer.