Live Voicemail in iOS 17 allows you to see real-time transcriptions of messages as they are being left, enabling you to decide whether to pick up the call. You can turn Live Voicemail on or off in the Settings app under the Phone section, and it is enabled by default in iOS 17. Voicemails are transcribed and stored in the Voicemail tab of the Phone app, where they remain as long as you keep them.