Three tiers in one
When Apple presents Siri AI as a single thing, the reality under the hood is more layered. Popular Science precisely summarized the three hardware tiers that emerged from the keynote's technical notes. The first tier — basic Siri AI — requires iPhone 16 or later, or iPhone 15 Pro or Pro Max: essentially any device with Apple Intelligence already active. The second tier extends Siri AI to iPad with M1 or later chip, Mac with M1 or later, Apple Watch Series 10 or later (with an Apple Intelligence iPhone nearby), and Apple Vision Pro.
The third tier is what separates the demo from what many users will actually see: customizable voices with modular expressiveness and the dictation accuracy leap are reserved for iPhone Air, iPhone 17 Pro and iPhone 17 Pro Max — not yet available at WWDC time — plus iPad with M4 or later chip and Mac with M3 or later having at least 12GB of unified memory. As Popular Science notes, anyone who bought a mid-range iPhone in the last couple of years should read the fine print carefully before getting attached to the keynote demos.
Why it matters
The stratification is not new in Apple Intelligence history, but this time it is internal to a single feature presented as unified. The communication risk is that the majority of iOS 27 users will perceive themselves as having Siri AI but find themselves facing an assistant noticeably less capable than the one shown on stage. Upfront transparency would have avoided disappointment; a footnote in the press release is not enough.