Apple still doesn’t let users replace Siri as the default assistant on the iPhone, but there is a simple workaround that gives you instant access to ChatGPT through the Action button. If you have an iPhone 15 Pro or a newer Pro model, you can assign ChatGPT’s voice mode to the Action button and launch it with a single long press.
OpenAI recently unified voice and text chats into the same window(Photo: Adobe Illustrator)
This turns the Action button into a shortcut to a faster, more conversational assistant that many users find more capable than Siri.
Here’s how to set it up.
How to assign ChatGPT to the Action button
Step 1: Install ChatGPT
Download the ChatGPT app from the App Store, then sign in or create a new account.
Step 2: Open iPhone Settings
Launch the Settings app on your iPhone.
Step 3: Go to the Action Button menu
Tap Action Button to open Apple’s control selection interface.
Step 4: Choose a custom control
Swipe to the Controls section, then tap the small chevrons next to the currently selected control.
Step 5: Search for ChatGPT
Use the search field to type ChatGPT.
Step 6: Select Open ChatGPT Voice
Choose Open ChatGPT Voice from the list.
That’s it. A long press of the Action button will now launch ChatGPT in voice mode.
What happens when you press the Action button
The first time you trigger the shortcut, the ChatGPT app may request microphone access. Tap Allow, and from then on, you’ll jump directly into a voice conversation the moment you press the Action button.
OpenAI recently unified voice and text chats into the same window, so spoken responses now appear on-screen alongside generated text or visuals. You can switch between talking and typing without losing context.
You can leave the app mid-conversation
If you swipe away from ChatGPT during a voice chat, the session continues in the Dynamic Island, where you can see it listening or preparing a reply. You can tap the island to return or end the session.
What ChatGPT still can’t do
This shortcut gives you a quick way to access a smarter assistant, but there are limits. ChatGPT still can’t perform system-level actions like:
-Setting alarms
-Changing device settings
-Reading your calendar
-Sending messages through iMessage
-Those remain exclusive to Siri.
Still, for deep responses, creative tasks, explanations, planning, and natural conversations, ChatGPT on the Action button is the closest thing to having a next-gen AI assistant built into your iPhone.