Mobile Lab: Responsive Testing & Screenshots

Test responsive websites across viewport sizes, capture screenshots, record QA flows, and inspect frontend issues.

Test responsive websites across multiple viewport sizes without juggling dozens of browser windows. Mobile Lab is a Chrome responsive testing and frontend-QA workspace for developers, designers, QA engineers, freelancers and agencies. Enter a URL, run representative coverage, compare multiple viewport states side by side, capture screenshots, record reproducible QA flows and inspect frontend issue evidence. DEVICE COVERAGE Use the maintained device catalog to choose representative phone, foldable, tablet, wearable and desktop viewport states. Each preset shows its source and verification status so responsive targets are not presented as physical-device certification. Search the catalog by model, manufacturer, form factor or alias, or use filters when you need a narrower test set. FAST RESPONSIVE TESTING * Standard Coverage starts with representative phone, foldable, tablet and desktop layout-risk classes. * Mobile, Foldables, Tablet and Desktop scopes provide one-click focused coverage. * Breakpoint Sweep checks 320, 360, 375, 390, 412, 768 and 1024 CSS widths. * Sync scroll, Sync rotate, Frames and Zoom stay available directly above the canvas. * Custom viewport presets remain available when named-device presets are not the right test. FOLDABLES Test explicit outer/cover and inner/open states for supported foldable layouts. Device descriptors record source and verification status so physical display specifications are not misrepresented as manufacturer-certified browser CSS behavior. SCREENSHOTS AND EVIDENCE * Capture one viewport or all visible screens. * Save or copy screenshots locally. * Redact and annotate before sharing. * Pro adds full-page and advanced evidence workflows. REPRODUCIBLE QA FLOWS Record navigation and click steps while keeping typed form values out of saved flow evidence. Protected password/payment/security steps do not receive screenshots. RESULTS Free includes deterministic responsive/frontend issue evidence. Pro adds deeper cause/fix/retest guidance, professional exports and developer/agent-ready handoff. LOCAL-FIRST PRIVACY Routine screenshots, QA-flow evidence and saved workspaces stay local unless you explicitly export, copy or invoke a supported Pro diagnostic action. Optional aggregate product telemetry is off until explicit consent and excludes tested URLs/hostnames, page content, screenshots, form values and credentials. ACCURACY NOTE Mobile Lab is responsive browser emulation, not physical-device certification. Current-device presets may include derived CSS viewport candidates when a manufacturer publishes physical display specifications but does not publish a browser CSS viewport. Those candidates are labeled in-product. Critical browser/device journeys should still be verified on the required real device. Support: [ml.support@marsci.cc](mailto:ml.support@marsci.cc) Privacy: https://ml.marsci.cc/privacy Terms: https://ml.marsci.cc/terms Refunds: https://ml.marsci.cc/refund Data disclosure: https://ml.marsci.cc/data-disclosure