I’ve been banging my head against this for months. I have been using Flutter, Firebase and the emulator for years but I can’t get a physical Android device to connect to the firebase emulator. I get this error on Windows 10.
[OnlineStateTracker]: Could not reach Cloud Firestore backend. Backend didn't respond within 10 seconds
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<p>An Android emulator has no issue connecting. The physical device can connect to the cloud Firestore with no issue. The only connection it can't make is from a physical device connected via usb to the Firestore emulator. I made the <a href="https://github.com/bradintheusa/emulator_test" rel="noreferrer noopener" target="_blank">most minimal example here</a> with no permissions or security to simplify the problem. It has the fixes I've seen others post (ssl, ports, ip address etc) but none work for me.</p>
<p><a href="https://rightclick.com.au/2022/02/16/firebase-emulator-and-physical-android-device/">Follow up post with solution</a>.</p>