In a video on YouTube, Google’s John Mueller suggested that you should migrate your m.example.com subdomains for mobile websites to responsive before Google releases the mobile first index.
Google currently indexes your desktop site and the m. subdomain of your site isn’t fully indexed. When Google’s index goes mobile first, the m. subdomain of your site will be the main version of your website and a migration to www might take months.
Currently, you can just redirect the m.-version of your site to the www.-version. You can view the statement here:
On Twitter, John Mueller added that the mobile pages should be fully equivalent in content and functionality regardless of indexing. If that is not the case now, you should fix your pages.
The mobile pages should be fully equivalent in content & functionality regardless of indexing, right? Why wait to fix that? Users care too.— John ☆.o(≧▽≦)o.☆ (@JohnMu) 19. Juni 2017
Check how your website looks on different devices
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