Visual Voicemail for iPhone
https://support.apple.com/kb/HT204039">If your carrier supports Visual Voicemail, you can set it up with these steps:
- Go to the Phone app, then tap the Voicemail tab.
- Tap Set Up Now.
- Create a voicemail password, then tap Done.
- Enter your password again to confirm it, then tap Done.
- Select Custom or Default. If you choose Custom, you can record a new greeting.
- Tap Done to save your greeting.