Photo: Bokeh / Tomedia. Old Brick Building with Balconies.
There is a fairly cheap website audit available to most business owners. Open the site on your phone and try to do the thing you expect a customer to do.
Read the service information. Find the price or the explanation of how pricing works. Open the menu. Fill in the form. Try to correct a mistake in the form. See whether the button stays where you thought it was when another part of the page loads.
You may learn more from that exercise than from another screenshot of the homepage looking excellent on a designer’s large monitor.
Fitting on the screen is the beginning
A responsive layout can rearrange the page without making it pleasant to use. Text can technically fit while being too small. A menu can open while covering the control needed to close it. A form can have all the right fields while making the person repeatedly zoom and pan to complete them.
These are ordinary usability problems. I don’t need to claim that each one corresponds to a secret ranking weight to think they deserve attention. A person trying to contact the business is already on the website. Losing them because the form is awkward is a practical failure with or without a search consequence.
Check a real task from beginning to end. A static image won’t show you how a keyboard changes the available space, whether an error message is visible or whether the confirmation gives the person a sensible next step.
A slow page becomes harder to tolerate when the controls are awkward as well. Fixing the layout while leaving the form painful to use still leaves you with a painful form.
Keep the information available
Google uses the mobile version of a site’s content for indexing and ranking. Its mobile-first guidance recommends equivalent primary content and meaningful headings across mobile and desktop. It explicitly allows a different layout, including tabs and accordions to save space.
So I wouldn’t remove useful information merely to make the mobile screenshot look cleaner. Arrange it in a way that works. If an accordion helps someone manage a long explanation, use one. Make sure the information is actually available to be loaded and read, rather than requiring an interaction before the site even fetches the primary content.
There is a difference between presenting the same information compactly and giving phone users an incomplete page. The person using the smaller screen may need exactly the same detail as the person at a desk.
I would also keep the central purpose easy to see. The opening doesn’t have to contain every condition, policy and technical specification. It should give somebody enough information to recognise the page they chose and decide where to go next.
The overlays count as part of the page
The newsletter prompt, cookie controls, chat widget and special offer all occupy real space. On a phone, there isn’t much space to share. Each component may look reasonable in isolation while the combination becomes exhausting.
Try the experience as a new visitor, where appropriate, as well as in the browser that has already dismissed everything. The business owner’s familiar view can hide the first-visit experience a customer is getting.
Then make a judgement about priority. If somebody came to enquire about a service, allow them to understand the service and reach the enquiry. Every extra thing you put in front of that route needs a reason to be there.
Give the person testing it a job
“Check mobile” is vague enough that it can mean dragging a browser window narrower and deciding the layout hasn’t broken. “Find this service and complete its enquiry form” is much easier to assess.
Write down the places where you hesitated, missed a control or had to work around the design. Fix those, then repeat the task. You don’t need to wait for the next redesign to remove an obstruction people are already encountering.
I cover the wider mobile and usability checks in The Big Book of SEO on Ephemera. You can buy the book there, but you can start finding the obvious problems now. Put the phone in your hand and try to use the site.