Apple this week revealed what its most advanced on-device AI model does, and the feature list is shorter than the hardware requirements might suggest.
In its Siri AI announcement during WWDC 2026, Apple confirmed that the model powers two things: more expressive Siri voices and a major accuracy gain for systemwide dictation.
Both require 12GB of unified memory. Among current iPhones, that limits the more powerful AI model to the iPhone Air, iPhone 17 Pro, and iPhone 17 Pro Max, alongside iPad models with the M4 chip or later, Macs with M3 or later, and Apple Vision Pro with M5.
That's right, the standard iPhone 17 misses out. Having only 8GB to its name – the minimum Apple Intelligence has required since launch – the base flagship model falls short of the new threshold. This is the first time Apple has raised that bar, given that Apple Intelligence has required 8GB since its introduction two years ago.
So What Does 12GB Get You That 8GB Doesn't?
On the voice side, users can adjust the expressiveness and pace of Siri's speech so that the assistant sounds the way they want it. However, it's the dictation feature that includes the more substantial change. Apple's most advanced on-device AI model is said to be able to turn speech into polished text on the fly, handling capitalization, punctuation, and formatting automatically, with improved speech understanding that's meant to cut down on errors.
Everything else in the Siri AI rollout – personal context, onscreen awareness, web answers, the dedicated Siri app, Visual Intelligence, and Writing Tools – runs on the broader Apple Intelligence device list. That list still includes iPhone 15 Pro, the iPhone 16 series, and iPhone 17.
The 12GB requirement, in other words, does not refer to Siri AI wholesale; it improves how Siri sounds and how well it transcribes. Base iPhone 17 owners will still get the new chatbot-style assistant with iOS 27, they'll just get the older voices and a less precise dictation engine.
Whether that matters will vary from user to user, but for anyone who dictates messages and notes all day, the better transcription is the kind of thing you will likely notice immediately. For everyone else, the difference may be something they can quite happily live with.
iOS 27 is currently in developer beta, with a public beta launching next month and a general release arriving in the fall.
