Mobile View: Device Emulator & Responsive Tester

Free, open-source mobile simulator and responsive tester for phone, tablet, laptop, and desktop views side by side.

Mobile View is a free, open-source device emulator and responsive tester for Chrome. Use it as a mobile simulator to preview a website in phone, tablet, laptop, and desktop views side by side—without repeatedly resizing a window or switching Chrome DevTools presets. Use this mobile simulator and responsive tester to catch breakpoint, overflow, navigation, and content issues while you build. Everything runs locally in your browser: no account, subscription, analytics, telemetry, or remote application backend. Click the extension icon or use the Chrome context menu to open the current website inside realistic device frames. The multi-device preview appears over the current tab, so you can check mobile view and desktop breakpoints in one workspace and return to the page when you close it. **Responsive website and mobile view testing** - Compare up to four device previews side by side in resizable panels. - Test phone, tablet, laptop, and desktop layouts at realistic viewport sizes. - Switch device, orientation, zoom level, and reload state independently. - Synchronize page and matching nested-container scrolling across previews when checking long pages. - Create custom viewport sizes for project-specific breakpoints. **Realistic device previews** - Preview iPhone, Android, iPad, tablet, MacBook, laptop, and desktop layouts. - Use device frames with platform-appropriate status and browser chrome. - See viewport dimensions and resize comparison panels directly. **One-click comparison sets** - Open Phone + Tablet, iOS + Android, or Mobile + Tablet + Laptop comparisons from the toolbar. - Save named device sets for repeated responsive QA. - Reuse custom device configurations from local Chrome storage. - Favorite frequently used devices, reopen recent devices, reorder viewports, or focus one viewport without rebuilding the workspace. **Screenshots and annotations** - Capture the active viewport or complete multi-device comparison. - Annotate with pen, rectangle, arrow, text, and crop tools. - Copy the result to the clipboard or download it locally. **Responsive behavior and physical-device handoff** - Synchronize scrolling, supported interactions, and navigation across matching previews. - Save reusable device sets for repeatable checks. - Open the current URL on a physical phone using a locally generated QR code. **Generate a responsive fix prompt** - Describe the expected and actual behavior once. - Automatically include the optional selector, device names, viewport sizes, orientation, and page URL. - Copy a structured fix prompt to Codex, Copilot, Cursor, Claude, or another coding tool. - Nothing is uploaded; the handoff uses your local clipboard. **Compare a reference with the live website** - Place a previous screenshot or approved design on the left. - Keep the current website interactive in the device previews on the right. - Import local design references for each viewport, compare them beside or over the live page, manually align overlays, and mark feedback locally. - Reference images and overlay settings stay in local Chrome storage so the workspace can resume; nothing is uploaded. **Privacy-first by design** - Free to use. - Open source under the MIT license. - No account required. - No backend service. - No analytics, telemetry, or remote logging. - Screenshots, recordings, URLs, annotations, designs, and settings are never sent to a backend. - Preferences, presets, recents, custom devices, design references, and UI state are saved locally in Chrome storage.