How to improve mobile search performance?

[nickreynolds]

Website is for a small local business.
The business is number one in the Google local business listing whether you search in mobile or desktop.
Searching from a desktop it is on page one of serps for most useful keywords - position 6-8
Searching from a mobile it is on page two of serps for those keywords - positions 12-15
The site is built with Wordpress and so uses a responsive theme.
I have done everything i can to improve load speed etc - compress images, caching etc etc -it scores pretty well on Googles mobile friendly test and others.
The site is well optimised for search but by no means overoptimised.
The site is about 8 or 10 years old. It used to rank in top 2-3 positions but has slipped in recent years.

This disparity between search results has been apparent for a number of months.
Any thoughts on the possible cause?

[nickreynolds]

Just to add - position one in google is a national franchise, position 2 scores "poor" 9 seconds on the new google mobile test!

[not2easy]

One place to check when things don't seem to be doing as well as they "should" be doing is to look at "Blocked Resources" in GSC. One WP site where I help out recently started dropping in the serps for no obvious reason and we found that the Mobile Friendly test scores were deceptively comforting. The blocked resources were due to some responsive features' /jquery/ files that showed up as Blocked by robots.txt. It was probably due to a child theme update. That may not be the case for you, but if it is, the update to robots.txt went to work immediately to get traffic and position where it had been for years so it's worth checking.

[keyplyr]

Searching from a desktop it is on page one of serps for most useful keywords - position 6-8
Searching from a mobile it is on page two of serps for those keywords - positions 12-15

This may likely change soon. Your mobile ranking will be what Google will use for both mobile & desktop searches. Read this:

Are you ready for the Mobile-First Index? [webmasterworld.com]

[nickreynolds]

Have made a few tweaks and it's now on page one on mobile (but still lower than desktop).
Is it possible that because the mobile version (responsive) has a dropdown for navigation and the site has no other internal linking from the homepage that that is affecting ranking? One of the tweaks i made is to add some internal links from the homepage

[keyplyr]

Your responsive navigation is unlikely to have caused a lower ranking than desktop.
All (most?) responsive pages do that... if you're using the mobile hamburger and not some older type of utility for navigation.

[whitedove is]

Have you looked at AMP, ( Accelerated Mobile Pages )?

Google will cache AMP to speed up service for Mobil devices. Almost all of the pages that show up on my Android are Google Cache AMPs.

[developers.google.com...]

Ampbyexample has lots of pointers, including checking that external resources load, clearly if they are not loading with an AMP proxy is used the site is not taking advantage of this service.

[ampbyexample.com...]

[Peter_S]

it scores pretty well on Googles mobile friendly test and others.

Did you try : [testmysite.withgoogle.com...]