Mobile & responsive checklist

For most sites, mobile is not a secondary experience—it's the primary one. A site that merely "works" on mobile isn't good enough; it needs to be genuinely comfortable to use on a small touchscreen.

Responsive fundamentals

• A correct viewport meta tag is present (width=device-width, initial-scale=1) so mobile browsers don't fake a desktop-width page
• Layout adapts cleanly across common breakpoints—phone, tablet and desktop widths—without horizontal scrolling
• Text is legible without the visitor needing to pinch-zoom
• Content reflows into a single, logical column on narrow screens rather than being squeezed
• Layout has been checked at the awkward in-between widths, not just the extremes of "phone" and "desktop"

Touch targets & interaction

• Buttons and links are large enough, and spaced far enough apart, to tap accurately with a finger
• Menus, dropdowns and any hover-based interaction from desktop also work with tap on mobile—nothing depends on a mouse hover to be usable
• Forms use appropriate mobile input types (email, tel, number) so the correct keyboard appears automatically
• Sticky headers or footers don't eat up excessive screen space on small devices
• Swipeable or draggable interface elements have a clear, non-gesture-dependent fallback way to accomplish the same action

Mobile navigation patterns

• A collapsed ("hamburger") menu, if used, is instantly recognizable and opens with a single tap into a clear, scannable list
• Primary actions and navigation sit within comfortable thumb reach on a typical phone, rather than requiring an awkward stretch to the far top corner for everything
• Search, if it's a primary way visitors find content, is easy to reach from anywhere in the mobile navigation, not buried several taps deep
• Bottom navigation bars or fixed action buttons, where used, don't overlap or obscure content as a visitor scrolls
• Deep navigation hierarchies collapse sensibly on mobile—a visitor should never lose track of where they are in the site on a small screen

Mobile content & layout

• The most important content and calls to action are visible near the top on mobile, not buried below unrelated elements
• Tables and wide content scroll within their own container rather than breaking the page's layout
• Pop-ups and interstitials don't cover the whole screen in a way that's hard to dismiss on mobile
• Images and media scale to fit the screen rather than overflowing or forcing horizontal scroll

Mobile forms

• Forms are shortened to what's genuinely necessary on a small screen—every extra field is more friction on mobile than desktop (see the conversion & forms checklist)
• Autofill and autocomplete attributes are set correctly so returning visitors aren't retyping information mobile browsers already have
• Date pickers, dropdowns and other custom controls use the device's native input where practical, rather than a fragile custom widget that fights the on-screen keyboard

Mobile performance

• Page speed has been tested specifically on a throttled mobile connection, not just desktop broadband (see the performance checklist)
• Large, unnecessary assets aren't served to mobile visitors who don't need them
• Tap responsiveness feels immediate—no noticeable lag between a tap and the resulting action
• Data usage is treated as a real cost to the visitor, not just a speed metric—unnecessarily heavy pages are a genuine burden on limited or metered mobile data plans

Mobile-specific SEO

• Since indexing is mobile-first for virtually all sites today, the mobile version of a page carries the content and structured data that matters—nothing important is hidden or removed on small screens
• Interstitials or app-install banners don't block content from being genuinely accessible to a mobile visitor arriving from search
• Tap-to-call and tap-to-map links work correctly for phone numbers and addresses

Testing

• The site has been checked on at least one real phone and one real tablet, not only a browser's device-simulation mode
• Both portrait and landscape orientations have been checked where relevant
• Forms, checkout flows and navigation menus have specifically been tested by hand on a touchscreen
• The site has been tested on more than one mobile browser, since rendering can differ—see the QA & cross-browser checklist
• On-screen keyboards have been checked against real forms to confirm they don't cover the field currently being filled in, or the submit button once typing is done

Mobile experience overlaps closely with performance and accessibility—a site that's fast and accessible is usually most of the way to being genuinely mobile-friendly too.