Technical guide
Mobile SEO
Google indexes the mobile version of your site. If your mobile pages show less than your desktop pages, the missing part effectively does not exist.
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Mobile-first means mobile-only, in effect
Google crawls and indexes using a mobile user agent. Whatever your mobile page contains is what gets considered. Desktop-only content is not a bonus; it is invisible.
This matters most on sites that hide sections on small screens to simplify the layout. Collapsing content behind an accordion is fine, because it remains in the HTML. Removing it from the mobile DOM entirely is not.
The parity checks worth running
Compare the mobile and desktop versions for body content, headings, structured data and internal links. Internal links are the one most often lost, because simplified mobile navigation quietly removes paths Google was using to find pages.
Usability still counts
Tap targets large enough to hit, text large enough to read without zooming, and no horizontal scrolling. These are not ranking factors in any direct sense, but they decide whether the visit is worth anything.
Common questions
Does hidden content on mobile still count?
Content inside an accordion or tab counts, because it is in the HTML. Content removed from the mobile page entirely does not.
Do I need a separate mobile site?
No. Separate mobile URLs are a legacy pattern that creates parity and duplication problems. Responsive design is the standard answer.
Where to next
If you would rather have someone do this than read about it, the commercial page for this work is Technical SEO services.
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