Mobilegeddon (April 21, 2015) — mobile-friendly pages boosted in *mobile* search results; ranking effect modest but successful as a forcing function for responsive design

Claim: The "mobile-friendly update" — nicknamed Mobilegeddon — rolled out April 21, 2015, boosting mobile-optimised pages in mobile search results (it did not affect desktop). Google pre-announced it in February 2015. Actual ranking impact was milder than the hype — Searchmetrics measured an average shift of ~0.21 positions for non-mobile-friendly sites — but it succeeded as a forcing function: huge numbers of sites went responsive. Google later moved to mobile-first indexing (announced 2018).

Source: Google Webmaster Central announcement, February 2015; Searchmetrics post-rollout analysis, 2015.

Confidence: Verified.

Why this matters for Candid: Cleanest "adapt or lose" beat for the SMB narrative — many local businesses ran old desktop-only sites and Mobilegeddon meant a mobile rebuild became table stakes. Drove by user behaviour (mobile had overtaken desktop) as much as by Google.