With news that OpenAI's ChatGPT Voice feature is now available to all free users, you can ditch Siri as your main voice assistant on your iPhone -- well, specifically on your iPhone 15 Pro and Pro Max, that is. Apple's latest smartphones support the ability to configure the new Action Button, which replaces the Mute button that has been on the iPhone since its debut. Depending on your personal preferences, you can associate the Action Button with any number of tasks -- it can open the Camera, turn on the Flashlight, record a Voice Memo, open the Magnifier app, allow you to quickly use an Accessibility feature or run an app Shortcut.