Mobile-first indexing and mobile friendliness

Most searches happen on phones, and Google crawls and indexes the web primarily as a smartphone. This is called mobile-first indexing.

Equivalent content

Google's best practices for mobile-first indexing:

• Same main content on mobile and desktop. Hiding content in tabs or accordions is fine.
• Do not lazy-load primary content only after an interaction (swipe, click, typing), because Googlebot does not interact.
• Same headings, titles and meta descriptions.
• Same structured data, using mobile URLs where they differ.
• Same robots meta rules. Never noindex the mobile version.
• Do not block resources that the mobile page needs to render.

Responsive design

Google recommends responsive design: one URL and the same HTML for every device, with CSS adapting the layout. It avoids almost every mobile-first problem. Separate mobile sites (m.example.com) need canonical and alternate annotations, matching status codes and twice the maintenance. They are rare today and best migrated to responsive design.

Mobile usability

Beyond indexing, a page that is hard to use on a phone loses visitors:

• A <meta name="viewport" content="width=device-width, initial-scale=1"> tag.
• No horizontal scrolling at phone widths.
• Readable text without zooming.
• Tap targets large enough and not too close together.
• No interstitials or pop-ups that cover the content as soon as the page opens. Google's starter guide advises against distracting ads and interstitials.

Lighthouse in PageSpeed Insights flags several of these on its mobile audit.