Hi there! I understand you're noticing that the listening function in the Substack app has disappeared on your device, which is running Android 10 with the WebKit browser engine. Let's see if we can get that sorted out.

To start, can you tell me a bit more about what you see when you open a post? Specifically:

- Are you able to see the play icon (usually at the top right of the post)?
- Have you updated the Substack app recently?
- Is this missing on all posts or just certain newsletters?

Meanwhile, here's a straightforward step-by-step guide to check:

1. Update the app: Make sure your Substack app is updated to the latest version from the Google Play Store. Sometimes features disappear due to outdated versions.

2. Check for the play icon: When you open a post, look for a small triangular play button usually on the top right. If it's missing, it could be:

- The publisher hasn't enabled audio for their posts.
- The app may have a temporary glitch.

3. Restart the app: Close the app completely and reopen it. Sometimes this refreshes features.

4. Clear app cache: On your Android device, go to Settings > Apps > Substack > Storage > Clear Cache. This can fix display issues.

5. Try reinstalling: If clearing cache doesn't help, uninstall and reinstall the app.

If after these steps the listening feature is still missing, it may be linked to specific newsletters not offering audio or a temporary app issue.

Could you please try those and share what you find? That way, I can guide you further, including checking for any known outages or escalations if needed.

Are you comfortable trying these steps?