Mobile-friendly update (2015): what changed and what applies now

What Google changed#

Google announced the change on 26 February 2015 in a Webmaster Central post: starting on 21 April, it would be “expanding our use of mobile-friendliness as a ranking signal,” a change that “will have a significant impact in our search results.” On launch day, Google’s rollout post said it was “boosting the ranking of mobile-friendly pages on mobile search results.”

Google defined mobile-friendly as pages where text is readable without tapping or zooming, tap targets are spaced appropriately, and the page avoids unplayable content or horizontal scrolling. The update affected only mobile rankings, in all languages, and applied “to individual pages, not entire websites.”

When it rolled out#

Google began the global rollout on 21 April 2015, as announced. It gave no completion date. On 16 March 2016, Google announced a follow-up that would, beginning in May 2016, increase the effect of the mobile-friendly ranking signal.

Mobilegeddon is not Google’s name. It came from the SEO industry: Search Engine Journal’s history of the update says several nicknames circulated before “Mobilegeddon” stuck. Google called it the mobile-friendly update.

What is known about its impact#

Google gave no percentage. Its own words were that the change would “have a significant impact” and that sites whose pages were not mobile-friendly might see “a significant decrease in mobile traffic from Google Search.” It also said query intent stayed a very strong signal, so a page with great content could still rank well without being mobile-friendly. Treat any figure attributed to this update as a third-party estimate.

What site owners should do#

Mobile-friendliness now sits inside Google’s page experience guidance, which asks “Does your content display well on mobile devices?” The same page says that beyond Core Web Vitals, other page experience aspects “don’t directly help your website rank higher,” though they make a site more satisfying to use. In practice:

• Make pages readable on a phone without zooming, with tap targets spaced apart.
• Avoid horizontal scrolling and content that cannot play on mobile devices.
• Work on Core Web Vitals, the page experience signal Google says its ranking systems use.
• Use Chrome Lighthouse to find mobile usability problems.

How to check whether it affected you#

This is historical: Search Console keeps 16 months of data, so it cannot show April 2015. If you kept analytics from then, compare mobile organic Google traffic for a week before 21 April 2015 with a week in May, and check desktop traffic stayed flat. The Google Algorithm Updates timeline lists the other updates of 2015, so you can rule them out first.

Related updates#

• The HTTPS ranking signal was the page experience signal before it.
• The intrusive interstitials update was the next page experience change, in 2017.
• The page experience update was the next page experience change, in 2021.