Recent iPhones and iPads that can use Apple's new AI features, branded Apple Intelligence, have a different version of Siri from that available on older iPhones and iPads. If your device supports Apple Intelligence you will find "Apple Intelligence and Siri" in Settings in place of "Siri". In iOS 18.3.2 this is available only in US English, UK English and English in Australia, Canada, New Zealand and South Africa. The only significant difference delivered so far in Siri with Apple Intelligence is its integration with ChatGPT, a major generative AI system produced by OpenAI, which brings powerful AI features to Siri but doesn't enhance Siri's limited capabilities to use your voice to interact with apps on your phone. The ability to interact more fully with apps on your phone with spoken commands was originally promised for a forthcoming version of iOS 18 but has been delayed; an early March 2025 Apple announcement stated that it will be available in "the coming year". So, for now, the two versions of Siri haven't diverged significantly. With the exception of the section on Apple Intelligence and Siri, I believe everything below should be applicable to both versions of Siri. I'll update these Siri pages as the versions diverge more significantly throughout "the coming year".