Mobile Lab: Responsive UX UI Checker

Preview and compare responsive web layouts across device viewports, run UX/UI review checks, capture evidence, and export reports.

Mobile Lab is a responsive website testing and frontend QA workspace for Chrome. Preview and compare websites across mobile, tablet, laptop, and desktop viewports, test responsive layouts and breakpoints, run UX/UI review checks, capture QA evidence, and export reports from one workspace. Built for frontend developers, UX/UI designers, QA testers, product teams, and agencies that need a faster way to test responsive websites across multiple screen sizes. KEY FEATURES • Responsive website testing Preview the same web page across multiple mobile, tablet, laptop, and desktop viewport sizes side by side. • Device and mobile preview Use a built-in device library and reusable viewport configurations to check how responsive layouts behave across screen sizes. • Breakpoint and multi-width testing Run Global Standard and multi-width views to identify layout, spacing, navigation, overflow, and responsive breakpoint issues. • UX/UI review Review usability and interface quality across all added screens with combined results and per-screen evidence. • Accessibility and frontend quality checks Surface accessibility-related issues and browser-side quality signals as part of the QA workflow. • SEO and AEO/GEO review Inspect structured frontend signals related to SEO, answer-engine optimization, generative-engine optimization, and page quality. • Accuracy Mode Explicitly trigger Chrome device and environment emulation for controlled frontend testing. • Screenshot and evidence capture Capture individual viewports or the full visible device set for bug reports, design reviews, QA evidence, and implementation handoff. • Saved QA workspaces Save and reopen repeatable responsive testing setups instead of rebuilding the same device matrix each time. • Reports and implementation handoff Export structured QA reports and turn findings into actionable evidence for developers or AI coding tools. WHO IS MOBILE LAB FOR? • Frontend developers testing responsive layouts and breakpoints • UX/UI designers reviewing implemented interfaces • QA testers checking websites across screen sizes • Product teams validating web releases • Agencies reviewing client websites • Developers looking for a faster alternative to repeatedly resizing one browser window FREE AND PRO Mobile Lab includes free responsive testing tools for core device preview and QA workflows. Mobile Lab Pro adds deeper review evidence, advanced reports, exports, saved workflows, and additional QA capabilities. Pro subscriptions are purchased and managed securely through Stripe outside the Chrome Web Store. PRIVACY Mobile Lab is designed as a local-first QA workspace. It does not include advertising SDKs or behavioral analytics telemetry. User-selected web pages are accessed only to provide the responsive testing, inspection, and QA functionality requested by the user. Learn more: https://ml.marsci.cc/ Support: https://ml.marsci.cc/support Privacy: https://ml.marsci.cc/privacy