Google Duo is one of Google's most successful communication services, which is saying a lot considering how many previous messaging services they've canned. Duo is a very simple-to-use video-calling application available for Android, iOS, and the web, and since its release in 2016, it has become the default video calling app bundled with Google Mobile Services. Google recently added 1080p video calling support over 5G on the Samsung Galaxy S20 family of devices, as well as other features such as sending notes and doodles to your friends and family. One of the best features is the ability to send a short (up to 30 seconds) video or audio message to your contacts if they missed your call. Now, evidence has emerged suggesting that Google Duo will soon support adding captions to your messages.

Jane Manchun Wong, notable for her work in reverse-engineering many popular apps, shared a screenshot of a new Duo setting hinting at this capability. Her screenshot shows two new options in Google Duo's settings, which most importantly suggest that captioning video and audio messages will soon be possible. The video message feature was added to Duo almost two years ago followed later by audio-only messages. Below the toggle, the description states that the audio content will be sent to Google, but not stored by them, for transcribing the message. It doesn't seem that this feature will support captioning the audio during a live call, though. Another toggle suggests that you'll be able locally store videos, voice messages, photos, and notes that are sent to you in Duo. Both new toggles will be available under the new 'Message settings' subsection.

If you the own Google Pixel 4, Pixel 4 XL, Pixel 3, Pixel 3 XL, Pixel 3a or Pixel 3a XL, you can already use the built-in Live Caption feature to add captions to most audio being played on your device. That feature works entirely on-device and across apps. Nevertheless, this captioning feature in Duo is definitely welcome, especially for those users who don't have a recent Pixel device. The new feature hasn't rolled out yet, and it's unknown when it will be available. We'll definitely make note of when the feature is available.