“The website is responsive. It works on mobile.”

It’s a sentence we hear often from local business owners who’ve commissioned a website. And technically it’s often true — the site renders on mobile. But “renders” and “works well” aren’t the same thing.

The majority of visitors to a typical local business website come from mobile — often clearly over half according to the measurements we’ve seen. Not making the mobile experience really good is deliberately losing the majority.

Here are the ten concrete things that decide whether a site actually works on mobile.

1. Fast loading

Goal: under 2 seconds LCP (Largest Contentful Paint) on mobile.

This is the most basic. A site that takes 5 seconds to load on 4G has already lost 40% of visitors before the first pixel shows.

Measurable in Google PageSpeed Insights. If your site is over 3 seconds LCP — that’s where the improvement potential is biggest.

Common causes of slow mobile loading:

  • Too large unoptimised images
  • Heavy JavaScript libraries
  • Several tracking scripts (analytics, Pixel, Hotjar)
  • Slow hosting/server

2. Clickable phone

tel: links make the phone number clickable on mobile. One tap = a call starts.

Test: open your site on mobile. Tap the phone number. Does the call function start? If not, fix it.

This is one of the simplest but most impactful mobile fixes. Local customers often call directly from the search result — make it ridiculously easy.

3. 44px+ buttons

Apple’s Human Interface Guidelines (and Google’s Material Design) recommend a minimum of 44×44 pixels for tappable elements on a touchscreen. Smaller = hard to hit, frustrating to use.

This especially applies to CTA buttons, navigation links, and phone/email links.

4. Readable text without zoom

Body text at least 16 pixels. Subheadings proportionally larger. No text that requires zooming to read.

Common mistakes:

  • “Small” text at 11-12px (hard to read on mobile)
  • Footer text shrunk under 14px
  • Footnotes or “fine print” that becomes illegible

5. Forms with the right input types

On mobile, form fields should use the right input type to activate the right keyboard:

  • type="tel" for phone → numeric keypad
  • type="email" for email → email keypad with @
  • type="url" for website → URL keypad
  • type="number" for numbers → numeric keypad

This reduces friction dramatically. Forcing someone to hunt for the @ on a standard keyboard is friction.

6. No horizontal scroll

The site shouldn’t force the user to scroll sideways to see the content. This is a common symptom of bad responsive design — something (a large image, a table, a wide container) breaks out of viewport width.

Test: open the site on mobile. Try to scroll horizontally. If the site moves — it’s a bug.

7. Easy-to-navigate menu

Hamburger menus are standard on mobile. But they must:

  • Open and close clearly (not hang open accidentally)
  • Not cover critical content when open
  • Have sufficiently large touch targets (44px per link)
  • Have an obvious close button

Test your menu with your thumb, not the mouse. The real experience.

Cookie banners are required for EU visitors. But they should:

  • Not cover the main content (cover only the bottom 1/3 max)
  • Have clear choices (“Accept” and “Only necessary” — not just “Accept all”)
  • Be reasonably designed for mobile

A banner that covers the entire screen and requires complicated choices loses measurable conversions.

9. Images that load progressively

Images should be:

  • Optimised in format (WebP where possible, JPEG/PNG otherwise)
  • Compressed (75-85% quality is usually sufficient)
  • Lazy-loaded (images outside the viewport don’t load immediately)
  • Responsive (the right size is delivered based on device)

A page with a 5 MB image total is sluggish on mobile. An optimised version can often go down to 500 KB without visible quality loss.

10. Mobile-adapted CTA design

The primary CTA should be:

  • Visible on the first screen without scrolling
  • Large enough to tap (44px+)
  • Visually distinct from the rest
  • Concrete text (“Call 08-XXX”, “Book a time”) not vague (“More info”)

A sticky CTA at the bottom of mobile (always visible while the user scrolls) is a debated feature — it works for some, feels intrusive for others. Test for your specific site.

How to test yourself

Open your website on your own mobile. Not in desktop mode. The real mobile experience.

The practical first step

If you have many mobile friction points:

  1. List them all during a test session.
  2. Sort by biggest impact on conversion (phone, CTA, form first).
  3. Fix one at a time over the coming weeks.

Many mobile improvements are quick to fix — especially with an agency that has experience. The value accumulates with every improvement.

Want to go deeper? Read The website that actually creates customers for the whole picture, or What does a bad website cost? for worked examples on the hidden cost.