ARTICLE
The 5 Failures the Mobile-Friendly Tester Catches Most
The five most common mobile failures: bad viewport meta, small tap targets, illegible fonts, horizontal overflow, and interstitials — with fixes for each.
Jun 10, 20268 min read
Understanding Your Auditmobile friendly testmobile seocore web vitalsusability
Run Recon's Mobile-Friendly Tester on 20 client websites and you'll see the same five failures appear repeatedly. Not randomly distributed across the full spectrum of possible mobile issues — the same five, over and over, on sites built by different developers in different years with different stacks.
These five failures aren't rare edge cases. They're the default outcome when mobile is treated as an afterthought during development. Here's exactly what each failure means, how the tester surfaces it, and what it takes to fix it.
Failure 1: Missing or Incorrect Viewport Meta Tag
What it is: The viewport meta tag tells the browser how to scale and fit the page on a mobile screen. Without it, mobile browsers render the page at desktop width (typically 980px) and scale it down — producing an unreadable, tiny-text experience that requires pinching to zoom.
How the tester flags it: "Viewport not configured" or "Page is not mobile friendly: viewport not set." This is a binary pass/fail — either the tag exists and is correct, or the page fails mobile-friendliness outright.
The correct tag:
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