When Apple unveiled Siri AI at WWDC 2026, it positioned the assistant as a major step forward for on-device artificial intelligence. However, many iPhone owners were surprised to learn that the most advanced version of Siri will only be available on three devices: the iPhone 17 Pro, iPhone 17 Pro Max, and iPhone Air.
The reason comes down to hardware. Apple’s most powerful on-device AI model, known as Apple Foundation Models (AFM) Core Advanced, requires 12GB of RAM, a specification currently limited to those three devices.
What Makes These iPhones Different?
Apple has introduced two versions of its on-device AI model. Most Apple Intelligence-compatible iPhones will run the standard AFM Core model, while the latest premium devices gain access to the more capable AFM Core Advanced version.
Although both versions support the new Siri AI experience, the advanced model unlocks additional features that are not available on older hardware.
Voice Customization Becomes More Personal
One exclusive feature is enhanced voice customization. Users can adjust the pace and expressiveness of Siri’s voice, allowing it to sound faster, slower, or more enthusiastic depending on personal preference.
Other compatible iPhones will still offer multiple Siri voice options, but they will not provide the same level of customization available through the advanced model.
Better Dictation Is the Bigger Upgrade
Perhaps the more practical improvement is Apple’s enhanced systemwide dictation. The advanced model can automatically handle punctuation, capitalization, and formatting while users speak naturally.
For people who frequently dictate messages, notes, or emails, this creates a smoother and more accurate experience without requiring manual corrections afterward.
Older compatible iPhones will still support voice dictation through Siri AI, but Apple indicates that the advanced model delivers greater accuracy and intelligence.
The Hardware Gap May Grow Over Time
AFM Core Advanced is built on a significantly larger AI model than the standard version, giving it more computing power for complex on-device tasks. While Apple has only confirmed voice customization and advanced dictation as exclusive features for now, the company has left open the possibility that additional capabilities could arrive in future updates.
As Apple’s AI ecosystem evolves, newer hardware may continue receiving features that older devices cannot support.
Should Current iPhone Owners Be Concerned?
For most users, the answer is probably no. iPhones that support Apple Intelligence will still receive nearly all of the Siri AI features announced at WWDC 2026. The exclusive additions currently amount to a more customizable voice and a more advanced dictation system.
However, the announcement highlights Apple’s growing reliance on hardware capabilities to deliver AI experiences. As artificial intelligence becomes a bigger part of iOS, the difference between standard and premium iPhone models is likely to become more noticeable.
