iOS 27 Siri Extensions: Best AI Assistant for iPhone in 2026

Apple just dropped a bombshell for iPhone users. According to Bloomberg's Mark Gurman - confirmed by Reuters in late March 2026 - iOS 27 will let you plug third-party AI assistants directly into Siri through a new "Extensions" system. Claude, Gemini, ChatGPT, Grok, and Perplexity are all expected to be available. For the first time, your iPhone's built-in assistant can route queries to whichever AI you trust most. It's a genuine shift. But as you scroll through that Extensions menu trying to pick the best AI assistant for iPhone in 2026, there's a question worth asking first: what do you actually need your AI to do? What iOS 27 Siri Extensions Actually Change Before the hype runs away, it helps to understand what the Extensions system does - and doesn't do. Siri Extensions let you choose a preferred AI to handle the chat and Q&A side of Siri. Ask a question, get a smarter answer from Claude instead of Apple's own models. Request a summary, get Gemini's take. It's essentially a rout