During WWDC 2026, Apple confirmed that its most powerful on-device AI model is currently only compatible with the latest iPhone Air, iPhone 17 Pro, and iPhone 17 Pro Max.

The reason for the device limitation is that the AI model requires 12GB of RAM to run, and only the above iPhones have that amount. Unfortunately, the iPhone 17 misses out because it has 8GB of RAM.
That means iPhone 17 owners will not get two features that depend on the model: more expressive Siri voices and a major accuracy improvement for system-wide dictation.
Everything else in iOS 27's 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, but 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.
That shouldn't be the case for the iPhone 18 when it arrives next year. Two separate reports out of Korea suggest the next-generation base model will feature 12GB of RAM, giving the device access to the full suite of Siri AI features. The latest report also claims that Apple will not increase the $799 starting price, and instead plans to absorb the higher memory costs in a bid to increase market share.
The iPhone 18 is expected to arrive in spring 2027 alongside the iPhone Air 2 and the lower-cost iPhone 18e.

















