For most local businesses, a big share of visitors come on a phone. Check your own number in Google Analytics or Search Console. Google prioritizes mobile-friendly sites. And yet most websites still look like they were designed in 2015.
This is a competitive advantage you can steal immediately.
Why Mobile-First Indexing Changed Everything
In 2018, Google switched to "mobile-first indexing." Before that, Google crawled the desktop version of your site and ranked based on that. Now, Google crawls the mobile version and ranks based on that. (For more on this, check out our guide on improving your website speed.)
If your mobile version is broken, your desktop ranking doesn't matter. Google is evaluating you on a device you haven't been optimizing for.
The impact: many websites have mobile problems their owners don't know about.
Useful resource: Google's Mobile-Friendly Test
Useful resource: Google's mobile-first indexing guide
How to Audit Your Mobile Experience
Test 1: Google's Mobile-Friendly Test
Go to Google's Mobile-Friendly Test (free). Type in your URL.
It tells you:
- Is the page mobile-friendly? (Yes or no)
- What issues exist? (Typography, buttons, viewport, etc.)
This is your starting point. If it fails, you have obvious problems.
Test 2: Test on Real Phones
Browser emulation isn't real testing. A real iPhone and real Android phone will show problems that desktop pretend-testing won't. We cover this in more detail in our post about reducing your bounce rate.
Actually hold your phone. Scroll your site. Try to click buttons. Do the text and images look right?
Test 3: Check Core Web Vitals
Go to Google PageSpeed Insights (free). It grades your site on:
- LCP (Largest Contentful Paint): How fast does content load?
- FID (First Input Delay): How responsive is the page?
- CLS (Cumulative Layout Shift): Does the page jump around as it loads?
Poor scores kill rankings. Good scores help.
The Most Common Mobile Problems (And How to Fix Them)
1. Tiny, Unreadable Text
If someone needs to pinch-zoom to read your text, it's too small.
What to check: Is body text 16px or larger? Are headings big enough to read without zooming?
How to fix:
- Set minimum font size to 16px for body text
- Use responsive font sizes (text gets bigger on larger screens)
- Use a line-height of 1.5+ so text isn't cramped
2. Unclickable Buttons
Buttons that are easy to click on desktop are tiny and impossible to hit on mobile.
What to check: Can you tap buttons with your thumb without hitting something else? Are buttons at least 44x44 pixels?
How to fix:
- Make buttons at least 44x44 pixels (easy thumb target)
- Add padding around clickable elements (space between buttons)
- Don't put two buttons side-by-side if they're too close
- Make links obvious (underline or color change)
3. Horizontal Scrolling
No one should have to scroll sideways. Ever.
What to check: Load your site and try to scroll sideways. If you can, something's broken.
Common culprits:
- Tables that are too wide
- Images wider than the screen
- Code blocks or embeds not sized responsively
- Fixed-width containers
How to fix:
- Make tables scrollable (scroll just the table, not the whole page)
- Scale images to fit the viewport
- Wrap long code in
<pre>with overflow scrolling - Use CSS
max-width: 100%on containers
4. Slow Loading Speed
Mobile networks are slower than WiFi. If your site takes 5 seconds to load on WiFi, it takes 15 seconds on 4G.
What to check: Run PageSpeed Insights and check the Largest Contentful Paint (LCP) score. Should be under 2.5 seconds.
How to fix:
- Compress images (use TinyPNG or ImageOptim)
- Remove unnecessary JavaScript
- Minimize CSS files
- Use a CDN (content delivery network)
- Enable lazy loading on images below the fold
5. Autoplay Videos or Music
Autoplaying videos are invasive and kill performance. They also drain battery.
How to fix:
- Remove autoplay entirely, or
- Make autoplay muted-only (video can start, but no sound), or
- Only autoplay if user has high-speed connection (not on mobile data)
6. Pop-ups That Trap You
Interstitial pop-ups that cover the entire screen are annoying on desktop. On mobile, they're a nightmare.
Google penalizes sites with aggressive mobile pop-ups.
How to fix:
- Don't use full-screen pop-ups on mobile
- If you must use a pop-up, make it easy to close (big X button, not tiny)
- Consider a banner instead of a pop-up
- Only show pop-ups after user has engaged with content, not on page load
7. Desktop Navigation on Mobile
Your desktop menu (with 10+ menu items) doesn't work on mobile.
How to fix:
- Use a hamburger menu (three horizontal lines)
- Stack menu items vertically
- Make menu items large and easy to tap
- Test that the menu opens and closes smoothly
8. Not Respecting the Viewport
Some sites disable pinch-zoom or set a fixed viewport that makes everything tiny.
How to check: Your site should have this in the <head>:
<meta name="viewport" content="width=device-width, initial-scale=1">
If you see user-scalable=no, remove it.
9. Images Not Sized for Mobile
Images that look fine on desktop are massive files that load slowly on mobile.
How to fix:
- Use responsive images (
srcsetattribute) so mobile gets smaller versions - Compress images before uploading
- Use modern image formats (WebP)
- Lazy-load images below the fold
10. Forms That Are Hard to Fill
Mobile forms should be easy to complete on a tiny screen.
How to fix:
- One field per row (not two fields side-by-side)
- Use mobile keyboard types (email fields show @ symbol, phone fields show numbers)
- Make input fields large enough to see what you're typing
- Label fields clearly
- Let users input data before asking for it (easier on mobile)
Quick Mobile Checklist
Test these right now:
- [ ] Can you read text without zooming?
- [ ] Can you tap buttons easily with your thumb?
- [ ] Is there horizontal scrolling?
- [ ] Does the page load in under 3 seconds?
- [ ] No autoplay video/audio?
- [ ] Pop-ups aren't trapped?
- [ ] Menu is mobile-friendly?
- [ ] Images load fast?
- [ ] Forms are easy to fill?
If you fail any of these, that's a ranking problem.
The Mobile Performance Cascade
Fix these in order:
- First: Make it functional (no horizontal scroll, readable text, clickable buttons)
- Second: Make it fast (compress images, minimize code)
- Third: Make it smooth (fix layout shifts, reduce jank)
What Google Actually Measures
Google's Core Web Vitals tool (now PageSpeed Insights) measures three things:
- LCP: How fast the largest piece of content loads
- FID: How fast the page responds to clicks
- CLS: How much the page jumps around as it loads
If you're below the "Good" threshold on any of these, you're losing rankings.
The Real Cost of Bad Mobile
Every extra second of loading costs you visitors. On a phone, on a beach connection, people don't wait.
On mobile, where connection is slower, this compounds. A slow website on mobile isn't just annoying. It's a sales problem.
One Final Thing
Mobile-first doesn't mean mobile-only. Your desktop site still matters. But if you're optimizing for desktop and ignoring mobile, you're ignoring the device most of your visitors probably use.
The good news: Mobile optimization compounds. One fix unlocks another. Fix text size, users can read. They scroll further. They find your CTA. They convert. The work pays off immediately.
If you're unsure whether your site is truly mobile-friendly, talk to us. We can show you exactly what's breaking and what's holding you back from conversions.
Twin Fin Studio does AI automations, SEO & web design. We're a partner to hospitality and local businesses in Lombok, Bali and Belgium.
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