Apple revealed this week what its most advanced on-device AI model does, and the list of features is shorter than hardware requirements might suggest.
In its Siri AI announcement at WWDC 2026, Apple confirmed that the model enables two things: more expressive Siri voices and a major gain in accuracy for system-wide dictation.
Both require 12 GB of unified memory. Among current iPhones, this limits the most 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 is missing. With only 8GB under its belt – the minimum required by Apple Intelligence since its launch – the base flagship model does not meet the new threshold. This is the first time Apple has raised this 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. However, it’s the dictation feature that brings the most substantial change. Apple’s most advanced on-device AI model would be able to turn speech into polished text on the fly, automatically handling capitalization, punctuation and formatting, with better speech understanding intended to reduce errors.
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Everything else in the Siri AI deployment – personal context, on-screen sensing, web responses, a dedicated Siri app, visual intelligence, and writing tools – runs on the broader list of Apple Intelligence devices. This list still includes the iPhone 15 Pro, iPhone 16 series, and iPhone 17.
In other words, the 12GB requirement does not refer to Siri AI wholesale; This improves the way Siri sounds and the quality of her transcription. Base iPhone 17 owners will still benefit from the new chatbot-style assistant with iOS 27, they’ll just get the old voices and a less precise dictation engine.
Whether this matters varies from user to user, but for anyone who dictates messages and notes all day, the best transcription is the kind of thing you’ll probably notice immediately. For everyone else, the difference may be something they can live with just fine.
iOS 27 is currently in developer beta, with a public beta launching next month and a general release arriving in the fall.
