I am developing a simple web application which only records a voice from microphone but I have some trouble.
HTML5 voice recording function works well on chrome and
Since iOS11, Safari now supports Media Capture API:
New in Safari 11.0 – 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.)
Announcement by Apple - broken link as of Jul 2018
A copy of the announcement on someone's blog
Therefore recorder.js will work now.