Hi there! Sorry for that - I introduced a bug in the version you were using that resulted in Firefox for Android always using a Windows user agent. I fixed that, version 7.0.1 that's just been released, so that Firefox for Android correctly spoofs as Chrome for Android.

I get your wish for a manual mobile/desktop toggle - but I have no plans to introduce that for now. "Desktop mode" exists on Android, and I might explore tightly integrating with that instead.