Speaker/mic access in a web app, from phone

I am planning a tool that needs audio recording and playback, and will use Ionic Native Media (https://ionicframework.com/docs/native/media).

The app needs Google APIs, so an internet connection is necessary. It cannot be a standalone mobile app. So I think this can be published as a pure web application; no need to build and deploy through an app store. Phone users will access it through their browser. The app will be more convenient to use from a phone because you’re talking to it, and Ionic takes care of making it look like an actual mobile app.

Now my questions:

  1. Will phone users get speaker/mic function through their phone browser, just like PC users?
  2. If so, in my code for the web application, do I still need to add each platform like ionic cordova platform add android? Or is that also taken care of by the phone’s web browser?