Since more and more searches are happening on mobile devises, Google is trying to keep up with their users and make their search engine more user-friendly. Google is trying to appeal to the majority of its users, which are mobile device users. Google has started using a mobile search engine index as its mayor index to crawl the web.
Before we go further, let's define an index. It is the collection of pages/documents that a search engine has found working through the web through different links. In the past, Google has used a desktop view; but, now that more and more people are searching with mobile devices, Google has changed its strategy to search the web through a mobile view.
What Happens If You Don’t Have a Mobile Site?
From what we can find, Google is saying it's okay if you don't have a mobile site, they will search through your desktop site instead. However, it appears Google does want you to have a mobile site.
What If You Have Less Content on Your Mobile Site?
If you have a mobile site, you want to make sure it has the same quality of content as your desktop site. Google will crawl both your mobile and desktop sites and will rank your mobile site as lower quality site if you don't have similar information and content.
So, this could affect a lot of businesses and marketers. You want to start working on building your mobile sites. Google hasn't come out and said that this is exactly what will happen, but looking at where Google and our users are moving, it would be wise to stay ahead and work on the quality and content of your mobile sites.
What About Expandable Content?
For the desktop site, this didn't help their rankings with Google. In some ways, it may hurt sites; however, it appears that Google will encourage expandable content in mobile view if it is helps give the user a better experience on your site.
How Is This Going to Affect Rankings?
Google has stated multiple times that they don't expect this to affect rankings significantly; however, they are not promising that no change will occur on rank listing. This will take time and patience to see how this will affect sites.
When Will This Change Take Place?
Google will not come out and tell us exactly when this will be fully implemented. They are piloting this with multiple users right now to see how it will go. They will either speed the process up if testing goes well, or will slow the process down if the process does not go as smoothly.
It would be inferred that sites that are mobile-friendly will likely see a boost in their rank list compared to sites that aren't. We will see the full impact after its release and see the results.
How Can I Determine If Google Is Seeing My Mobile Site?
The best way to determine if Google has found your site is to go to the Google Search Console and use the Fetch and Render tool. You can use mobile:smartphone and look at the preview after you've completed the fetch and render. What Google displays in the rendered results is what Google has found and indexed about your mobile site. If you notice something is missing, then by all means work to fix this so that all your content is available to users.
Mobile vs. Desktop Indexes?
Ultimately, it looks like Google is going to try and have only one index. With Google making its move to prefer mobile sites, they will likely go to mobile index only in the future and the desktop index will be obsolete if the majority of users continue to search on mobile devices. Marketers need to work on improving mobile sites so they can get listed well.
You will likely not see any changes now. The ultimate start is anyone's guess, but by working on your mobile sites now and staying ahead of the game, you will be making the best choice.