The iPhone 15 and iPhone 15 Plus are both expected to be announced later in 2023 alongside the iPhone 15 Pro and iPhone 15 Pro Max, and it's now being said that we can expect the phones to borrow a feature from last year's best iPhones.
In 2022 the iPhone 14 Pro and iPhone 14 Pro Max both gained a new 48-megapixel camera, but the iPhone 14 and iPhone 14 Plus both had to make do with the 12-megapixel camera that everyone was familiar with from previous models. That's apparently going to change this year.

That's according to analyst Keff Pu from Hong Kong-based investment firm Haitong International Securities. Pu's research note was seen by MacRumors which says that the new 48-megapixel camera will use a three=stackes sensor that will allow it to capture more light, possibly resulting in improved image quality.
However, it's thought that recent supply chain checks have shown Pi that the stacked sensor system is suffering from a low yield during production - the result could be that the iPhone 15 and iPhone 15 Plus will suffer from production delays. Thankfully, it doesn't sound yet like the phones will miss the expected September 2023 announcement.
This year's non-Pro models are already expected to be impressive compared to previous models. Alongside the new camera, we're also told to expect the iPhone 15 and iPhone 15 Plus to gain the iPhone 14 Pro's Dynamic Island for the first time. It isn't expected that the 120Hz ProMotion display will also make the move down the lineup this year.