A Progressive Web App can be SEO-friendly, but service workers are not an SEO requirement and are not, by themselves, a Google ranking factor.

Dynamic rendering mobile SEO serves pre-rendered HTML to crawlers, while users may receive a client-rendered JavaScript experience.

According to early 2026 Chrome User Experience Report (CrUX) data, roughly 43% of websites still fail the Interaction to Next Paint (INP) threshold of 200 milliseconds, making it the most commonly failed Core Web Vitals.

The architecture of search has been fundamentally redefined, with desktop experiences no longer constituting the primary lens through which search engines assess relevance and authority.

In 2026, user expectations have peaked, Google’s AI-driven search generative experiences demand instant delivery, and the threshold for passing Core Web Vitals is aggressively unforgiving.

In the early days of SEO, a mobile site was often a stripped-down “lite” version of the desktop experience, a necessary compromise for slow 3G networks. Today, that compromise is a ranking death sentence.

While Largest Contentful Paint (LCP) measures visual load speed, Interaction to Next Paint (INP) measures interface responsiveness. High INP scores directly correlate with increased mobile bounce rates.