Apple wants to end the confusion that is its software numbering, and will start naming its numerous operating systems after the year following their release.
This is similar to the way automakers set the model year of their new vehicles to keep them fresh in the mind of the consumer for two years in a row. Just like Tesla named its newest facelift the 2026 Model Y, for example, Apple will reportedly call its next iPhone software iOS 26.
This will go for all of its operating systems, too, so instead of iOS 19, macOS 16, iPadOS 19, watchOS 13, macOS 15, or visionOS 3, Apple will use the WWDC 2025 event to announce iOS 26, macOS 26, and so on.
Samsung pulled something similar a few years back, but for its flagship phones. It jumped from the Galaxy S10 in 2019 to the Galaxy S20 in 2020 to start naming its handsets after the year of their release, making them sound more generationally advanced than Apple's iPhones, which are currently "only" in their 16th edition.
Microsoft also resorted to naming its Windows operating system after the year of its release at one point, but then reverted to sequential numbering again.
In any case, it remains to be seen if Apple will apply the same naming scheme for its iPhones, too, so that it jumps from the current iPhone 16 Pro Max to an iPhone 26 Pro Max running on iOS 26 in September.
The new iOS 26 is expected to feature a drastic visual overhaul, too, so there will be plenty new to see at WWDC 2025.