You can record a custom voicemail greeting right from the app (iOS only).
- Tap the Settings menu in the top-left of the upper toolbar.
- Tap Voicemail Greeting.
- Select Custom, then tap Record.
- Make your recording, then tap Stop.
- Tap Play to preview, or Record to try again.
- Once you’re happy with your greeting, tap Save in the upper toolbar.
It is not yet possible to customize your voicemail greeting from the Android app.