If you join a meeting and the Webex app detects that the battery of your device will run out before the meeting's scheduled end time, you'll be notified to switch to audio-only mode. Otherwise, use these steps to turn on audio-only mode at any time.
This feature is available when you're connected to the meeting audio with the Use computer for audio option.
Open settings from your profile picture, tap Video, and make sure that Audio-Only Mode is toggled on.
While connected to the audio portion of the meeting, swipe right to turn on audio-only mode.
Swipe left to turn off audio-only mode.
If you were muted when you turned on audio-only mode, you stay muted. Tap to unmute.
If you need to leave the meeting before it ends, tap Leave Meeting.