SEO Technical: Mobile-Friendly
Guides mobile-first indexing optimization and mobile usability. Google uses the mobile version of pages for indexing and ranking; mobile-friendliness is a ranking factor.
When invoking: On first use, if helpful, open with 1–2 sentences on what this skill covers and why it matters, then provide the main output. On subsequent use or when the user asks to skip, go directly to the main output.
Scope (Technical SEO)
- Mobile-first indexing: Google primarily crawls and indexes mobile version
- Mobile adaptation: Responsive design, viewport, breakpoints
- Content parity: Mobile and desktop content should match (or mobile preferred)
- Mobile usability: Viewport, font size, touch targets, no intrusive interstitials
- AMP: Accelerated Mobile Pages—status and when to consider
Initial Assessment
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Identify:
- Site type: Responsive, separate AMP, dynamic serving
- Content parity: Does mobile show same content as desktop?
- Tools: GSC Mobile Usability report; Mobile-Friendly Test
Mobile-First Indexing Requirements
Responsive Design & Mobile Adaptation
Responsive design = Single HTML; CSS media queries adapt layout to screen size. Preferred for SEO: one URL, no duplicate content.
Viewport
The viewport meta tag tells browsers how to scale and size the page on mobile. Required for mobile-friendly pages.
Without viewport: Desktop layout shrunk; horizontal scroll; fails Mobile-Friendly Test. See page-metadata.
Mobile Usability Checklist
Common Issues
Responsive vs. Separate URLs
Accelerated Mobile Pages (AMP)
AMP is a web component framework for fast-loading pages. Status (2024–2025): Still supported; no longer required for Top Stories or ranking.
Recommendation: For most sites, prioritize responsive design and Core Web Vitals over AMP. AMP adds maintenance (separate AMP HTML); modern optimization offers similar performance with more flexibility.
Output Format
- Mobile Usability status: Pass/fail from GSC or Mobile-Friendly Test
- Responsive / viewport: Check viewport meta; breakpoints; fluid layout
- Content parity: Mobile vs desktop content check
- AMP: Only if legacy or specific use case
- Fixes: Prioritized by impact
Related Skills
- page-metadata: Viewport meta tag; required for mobile
- core-web-vitals: CWV measured on mobile; replaces AMP for Top Stories; LCP, INP, CLS
- canonical-tag: Separate mobile URLs; hreflang for mobile
- image-optimization: Responsive images; mobile LCP
- rendering-strategies: SSR/SSG for fast mobile load
- google-search-console: Mobile Usability report
