A mobile layout issue is any visual or functional problem that appears on phone screens that doesn't appear on desktop. Common examples: text that overflows its container, images that are too wide for the screen, buttons that are too small to tap accurately, menus that don't close properly, and checkout forms with overlapping fields. These issues are invisible if you only test your store on a desktop browser.
65–80% of your traffic is on a phone. A single layout issue — a button that's 10px too narrow, a section that overflows on 390px screens — causes visitors to bounce before they can buy. Google also uses mobile layout as a ranking signal through Core Web Vitals (specifically Cumulative Layout Shift). A store that fails on mobile loses rankings and conversions simultaneously.
In Chrome on desktop: right-click → Inspect → click the phone icon at the top left of the inspector (toggle device toolbar). Set the device to "iPhone SE" (375px wide) and "iPhone 14 Pro" (393px) and scroll through your homepage, a collection page, and a product page.
Look specifically for: text that extends beyond the screen width, images wider than the viewport, buttons that are under 44x44 pixels (Apple's minimum tap target), and any horizontal scrollbar.
On an actual phone: visit your store in Safari on iOS or Chrome on Android. Try to actually complete a purchase — notice every friction point.
Use Google's Mobile-Friendly Test (search.google.com/test/mobile-friendly) for a quick automated check. But manual testing on real devices reveals more than automated tools.
In your Shopify theme editor (Online Store → Themes → Customize), preview your store on mobile using the mobile preview button. Walk through each section and adjust content, spacing, or column settings to fix visible issues.
For text overflow: in your theme code, find the section CSS and add overflow: hidden or word-break: break-word to the affected container.
For small tap targets (buttons, nav links, variant selectors): increase padding in the theme editor or via CSS. Apple recommends 44x44px minimum. Product variant buttons are the most common offender.
For images wider than the viewport: ensure all images have max-width: 100% in their CSS. In Shopify themes, this is usually set globally — check if a specific section is overriding it.
For checkout form issues: Shopify's checkout is largely controlled by Shopify, not your theme. For Plus stores, contact Shopify support. For non-Plus stores, ensure your theme's cart page is responsive by checking the cart.liquid template.
Testing only on desktop and assuming mobile looks the same — the most common reason mobile issues go undetected
Fixing the iPhone 14 display without testing smaller screens (iPhone SE at 375px is where most layout breaks happen)
Using fixed pixel widths for containers instead of percentages or max-width settings
Fixing the homepage and ignoring product pages, cart, and checkout — where mobile conversion happens
Not testing after each fix — changes to one section can affect adjacent sections
Critical
1–3 hours depending on severity
Intermediate
Trust Score Calculator
Free tool
Check this issue on your store right now — no signup required.
Broken Mobile Layout is just one of dozens of issues we check. Get your complete store audit.
Full Audit — $50Our full audit checks your mobile layout across tap targets, viewport configuration, Apple touch icon, and rendering issues — and flags the specific elements causing problems on phone screens.
Get Your Full Store Audit — $506 categories. Prioritized fixes. Under 60 seconds.