Google is displaying a new option to “search by photos” box in some local verticals only in mobile results and is labeled as interesting findings and discover more places.
No fixed position. In the above example, it shows below the fold, below local pack and other organic results. In a couple of cases, the search by photos box appears just below the local pack
Every image shows star ratings and distance from the user & on clicking it directly takes to the user over the google my business listing profile page. One more option of more photos is there which opens a full page of photos from different listings.
Another example of dentists:
Image source:searchengineland
Not showing for all categories. It is displaying this for just couple of categories and not displaying this for every category.
It’s still not clear whether Google is testing this or rolling out a new update for mobile SERP. Even the criteria of showing images are not cleared too. The Listings in local packs and searches by photos sometimes respond and sometimes did not.
Why Should We Care?
We should care because local business are in profits with this. Search by photos is another argument in favor of claiming and building out Google My Business Profiles with a lot of images.
2054 
