The iPhone 6s and 6s Plus both have higher levels of water resistance than previous models, but Apple didn't describe them as waterproof.
It's unclear from the report what kind of steps Apple is going to take to make the iPhone 7 waterproof, but it does describe "new compound materials" that will remove the outside antenna bands and could add water resistance by being less porous.
Apple has a "tick, tock" update strategy with the iPhone: The "tick" upgrades are big, new-number models (such as the iPhone 4, 5, and 6) that often add a new design, while the "S" models are "tock" upgrades that add smaller features (such as 3D Touch).
The iPhone 7, as the name suggests, will be the latter and adding waterproofing, which is already available on other Android handsets such as the Sony Xperia Z5, is a big feature Apple can talk about on-stage.
According to Sony, waterproofing is achieved by covering all ports - such as headphones and USB - and sealing the edges of the display so that water cannot seep in. Reports have suggested that Apple could be looking at creating "self-healing" seals that cover ports.
Reports have suggested that the iPhone 7 will launch in October 2016, have a new design, and could do away with the home button.
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