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What we know about Google’s mobile index.

The author

Malcolm Slade

Head of Technical SEO

Google has always worked with desktop web pages as its primary source of content, leading to our current situation where content is primarily ranked using desktop signals, with minor adjustments made for mobile queries based on ‘mobile-friendliness’.

This often leads to content ranking for mobile queries that is a poor shadow of its desktop variant, sometimes due to minimisation of content to fit a perceived user intent / experience.

With mobile query volumes now surpassing desktop, Google is looking to readdress the balance in favour of ensuring a solid user experience for mobile users that goes beyond simple ‘mobile-friendliness’ to ensure a user’s needs are met as they would be should they have searched on desktop.

A mobile index

For a while now, Google has talked about a mobile-oriented index. The general consensus in the industry has been that Google would run a separate desktop and mobile index with algorithms tailored to both.

However, Google has now announced that what it's actually doing in the next few months is making the primary index mobile-first. In effect, your ranking will be decided by how well your mobile site performs rather than your desktop variant.

This could potentially be a big deal as to date; certain assumptions have been made about how mobile users interact with web content leading to specific trends in mobile design, UX and information architecture.

Often, mobile sites are heavily focused on conversion in a similar fashion to desktop pages created specifically for PPC campaigns. Content is kept to a minimum, real estate is prioritised towards advertisement and conversion. The users know why they’re there, so distraction is kept to a minimum.

In this new mobile-first index, content relevance and quality will be assessed primarily within the mobile experience, requiring mobile and current desktop experiences to be much more closely aligned.

Gary Illyes, Google’s webmaster trends analyst, recently held a Q&A on Twitter to answer any burning questions. I’ve pulled out the key points from the session to look at what they mean for us in the industry.

What does this mean for sites without a mobile site?

Gary mentioned that desktop content will still rank, but it’ll have less value:

Gary Illyes tweet

It seems that desktop content will still have the potential to outrank mobile content, but mobile content will be favoured. 

Do we need to modify current rel=alternate / canonical tags?

Current practice is to mark the desktop version of a page as the canonical form via a canonical tag and the mobile version (if one exists) as an alternate form via a rel=alternate tag.

With a mobile-first index, it would make sense that these would be switched around, however, Gary answered:

Gary Illyes tweet

This makes sense, especially when you consider a later tweet on the same subject:

Will content elements such as tabs and accordions be devalued on mobile as they are on desktop?

Content that isn’t present to desktop users when a page first renders has been devalued for a while. It makes sense, as Google is stating that if you’re not willing to show the user that content straight away, it can’t be that important.

Mobile is different. On a mobile website, content is often placed within accordions and tabs to enhance UX and make overall better use of the available real estate. Here, it isn’t so much that the content isn’t worthy of being shown, but more of a case of providing a more beneficial UX to mobile users.

Google has considered this, and Gary tweeted:

The use of the word ‘hidden’ then caused the conversation to bend towards hiding content fully on mobile with no way to view it. Content in an accordion or tab that can be clicked to access isn’t hidden as such. I would suspect content fully hidden will continue to be ignored as it is within the current desktop index.

Will load speed be more of a factor within a mobile-first index?

I asked Gary this question, as to me, it would make a lot of sense for speed to have an impact for mobile users. After all, AMP is partly about allowing developing countries to experience the mobile web.

This is understandable as speed is a big part of mobile experience and adding complexity to mobile pages will have an impact on overall speed; expect to see even more sites shift to AMP.

Is there a confirmed launch date?

“Within months” was the original vague proposed date; Gary didn’t really expand on this or make a date clearer to those tweeting:

Given how big the change to the index is, I wouldn’t expect to see any form of rollout prior to March 2017. We even get a test index as we did with Caffeine.

Does this impact you?

If you’ve created a mobile site to serve your users in exactly the same fashion as your desktop site, whilst taking into consideration the differing UX expectation and frustrations of mobile then you should be fine.

Whilst I still don’t like the term ‘mobile-first’ (I prefer ‘audience-first’) it’ll be good to see more effort put into mobile sites with desktop and mobile being at least equal when it comes to design /  UX and information architecture efforts.

I also expect this and the recently announced rules regarding pop-ups and interstitial pages to have a positive impact on the mobile web as a whole.

In a nutshell, make the best site you can for your audience to interact with on whatever device they choose. This remains the best advice and it’s unlikely to change.