It looks like getUserMedia() is now the way to go for capturing audio recordings from a user.
But that leaves out Safari and iOS Safari.
Originally I had at
UPDATE: New in Safari 11.0 (iOS 11) – Camera and microphone access. Added support for the Media Capture API. Added ability for websites to access camera and microphone streams from a user's device (user permission is required.)
https://developer.apple.com/library/archive/releasenotes/General/WhatsNewInSafari/Articles/Safari_11_0.html