AlterBrains

hi, I wanted to ask a question before buying.I want to create a mobile (specific) version of my website on a subdomain. also i readed this case studie: https://alterbrains.com/joomla-extensio ... le-version
but i have some question:
1- Do I need to install a Joomla subdomain? Or is there no need for it?
2- Should I install the plugin on both websites (domain and subdomain)? Or only in the main domain?
thank you

This configuration means that you will have a single Joomla website which can be loaded via two domain names. Mobile subdomain will be a mirror of main site, but a subdomain will display customized contents.

Note that MightySites doesn't perform any redirects to mobile subdomain depending on the user agent device or browser settings.