For ChatGPT to function as a full-on voice assistant, you’ll need to subscribe to ChatGPT Plus which costs $20 a month. After subscribing, you have to go into the app and navigate into its Settings, then New Features, to turn on the Voice Conversations feature.
If you don’t want to pay, you can still set up the iPhone’s Action Button to open up the ChatGPT app, but you’ll only be able to interact through text. For a free, although not as advanced option, you can set up Google Assistant in the exact same way. Either way, we’re finally free of Siri and it’s all thanks to Apple.