Google has officially announced it will start using mobile usability as a ranking factor in mobile search.
This, its says, will have "a significant impact in our search results".
The announcement comes after months and months of tense speculation, fueled by Google's confirmation that it was 'experimenting' with the signal, and the instatement of 'Mobile-friendly' labels in mobile SERPS (search engine results pages).
Unusually, Google has given an official kick-off date for the algorithm - it will roll out globally (in all languages) on 21 April 2015.
'Mobile-friendliness': Google says it is "expanding our use of mobile-friendliness as a ranking signal", and "consequently users will find it easier to get relevant, high-quality search results that are optimised for their devices".
It's unclear whether this will take the form of a penalty for mobile-unfriendly sites, or a 'promotion' for mobile-friendly sites. But the end result will be widely similar: Sites that provide mobile users with a better experience will likely find themselves rising up the mobile search rankings.
A boost for indexed apps: Google's App Indexing service lets app creators build links to their apps within the SERPs. This only works for signed-in users who own the app, but nonetheless, indexed apps will soon appear more prominently in the search results.
Google says: "Starting today, we will begin to use information from indexed apps as a factor in ranking for signed-in users who have the app installed."
Stay tuned for more updates and advice.
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