In a few months’ time, you may begin to notice different sets of search results when searching on your phone compared to when browsing on your computer – even if you use the same terms. That’s because Google has decided to start indexing mobile websites separately.
The new mobile index will be classed as the primary route the search engine will take to respond to queries. A separate desktop index will be maintained, but will not be as up-to-date as the mobile index.
The news broke earlier this month during a keynote from Google Webmaster Trends Analyst, Gary Illyes. Illyes didn’t give a definitive timeline during his talk, but later confirmed that it would happen “within months.”
At present, it’s unclear exactly how the mobile index will work. For example, since the mobile index is the “main” index, will it really not be used for any desktop queries? Will it only contain mobile-friendly content? How out-of-date will the desktop index be? Desktop usage is a minority of Google queries, but still undoubtedly generates substantial usage.
The most substantial change will likely be that by having a mobile index, Google can run its ranking algorithm in a different fashion across mobile content rather than the current system that extracts data from desktop sites to determine mobile rankings.