Mobile-first indexing means Google predominantly uses the mobile version of your pages to index and rank them. In practice, your phone version needs the same content, images and structured data as your desktop version, plus readable text, usable buttons and reasonable speed. If something is missing on mobile, Google may never see it.
Mobile-first indexing means Google predominantly uses the mobile version of your pages when deciding what they contain and where they rank. If your phone version is thinner than your desktop version, Google is judging the thinner one. For most Christchurch businesses the fix is not a rebuild, just making sure nothing important disappears on a small screen.
What Google actually looks at
Googlebot visits your pages pretending to be a smartphone. What it reads there, the text, the links, the images, the structured data, is what feeds the index. Google has described this as the default for years, so assume it applies to your site.
This is separate from how people experience your site, but the two overlap. A page that frustrates visitors on a phone tends to lose them, and Google's guidance on helpful pages has always pointed towards a good experience on whatever device people use.
Content parity: the one that bites
The biggest risk is content that exists on desktop but not on mobile. It usually happens quietly:
- A designer hides a long description on small screens "to keep it tidy".
- A mobile menu drops secondary links, so Google sees fewer connections between pages.
- Images are swapped for smaller galleries, or alt text is missing on the phone version.
- Structured data or title tags differ between versions.
Say a Sumner cafe has a desktop menu page with full descriptions and dietary notes, but the phone version shows a short list of highlights. Google reads the short list. Anyone searching for a gluten-free brunch in Sumner will not find the page, even though the information exists on desktop.
Tabs and accordions are different. Google has said content tucked into them is fine on mobile, as long as it is in the page when it loads. Content that only loads after a tap, fetched from the server on demand, may never be seen by Google. Check with your developer if you are unsure how a section loads.
Images and structured data follow the same rule. If the phone version uses different image files, make sure they still have descriptive alt text. If you use schema markup for your business details or reviews, check it appears on the mobile version of the page too, because that is the version Google reads. Titles and meta descriptions should match across versions, so a plumber in Hornby is not described one way on a laptop and another way on a phone.
What a good mobile page looks like
None of this needs special tools. It needs a phone and a few minutes:
- A viewport setting. The page tells the phone to fit its width instead of shrinking a desktop layout. Most modern themes do this already.
- Readable text. You should not need to pinch and zoom to read a paragraph.
- Tap targets with room. Phone numbers, menu items and buttons should be big enough and far enough apart to hit with a thumb.
- No intrusive pop-ups. Google has said that pop-ups covering the main content on arrival can be a problem. A small banner is fine; a full-screen takeover on a service page is not.
- Sensible speed. Mobile connections vary, and Core Web Vitals are measured on real devices. See why a slow site costs customers for the fuller picture.
How to check your own site
- Open your five most important pages on a real phone, ideally on mobile data rather than your office wifi. Scroll the whole page and ask what is missing compared with your laptop.
- Open Search Console, paste a page address into URL Inspection, and run the live test. View the tested page and check the key text and images appear.
- Run the page through PageSpeed Insights and read the mobile results. It points to specific slow elements, not just a score.
- Check your images on mobile too. Image optimisation matters more when a phone is on a weak signal.
For the broader list of things to review, our technical SEO checklist covers where mobile fits.
Common mistakes and fixes
Hiding content to shorten the page. Fix: restructure it so it is shorter overall, rather than present on one device and absent on the other.
A stripped-down mobile menu. Fix: keep the same key links, even if they sit inside a collapsed menu.
Blocking resources on mobile. If CSS or image files are blocked from Google, it may not render the page properly. Your developer can confirm this from the URL Inspection output.
Redesigning without testing mobile first. A new theme often changes what mobile visitors see. Redesigning without losing your rankings explains how to test before you launch.
What this will not do
Passing a mobile check does not push you up the results by itself. It removes a way to fall behind. Rankings still depend on relevance, quality and competition. And a mobile-friendly page that says nothing useful is still a page that says nothing useful.
If you want someone to compare your mobile and desktop pages and tell you honestly what Google is missing, our SEO audits include that check, or you can ask for a free SEO audit and we will look at your top pages on a phone first.
