DeviceView Lab-MultiDeviceTest Autor: Mujahidul Islam

DeviceView Lab is a comprehensive, developer-focused responsive testing laboratory built specifically for Mozilla Firefox. It allows web developers, frontend engineers, designers, and QA testers to preview websites as if they were running on real smartphones, tablets, laptops, and desktop monitors.

KEY CAPABILITIES:

• 35+ Built-in Flagship Device Presets
Pre-configured with authentic CSS viewports, physical resolutions, and Device Pixel Ratios (DPR):
- Android: Samsung Galaxy S24, S24 Ultra, S25, S25 Ultra, Google Pixel 8, 8 Pro, 9, 9 Pro, 9 Pro XL, OnePlus 12, Xiaomi 14, Redmi Note 13 Pro, Nothing Phone (2), Motorola Edge 50 Pro.
- iPhones: iPhone SE (3rd gen), iPhone 13, iPhone 14, iPhone 15, iPhone 15 Pro, iPhone 16, iPhone 16 Pro, iPhone 16 Pro Max.
- Tablets: iPad 10th gen, iPad Mini, iPad Air 11", iPad Pro 11" and 13" (M4 Tandem OLED), Samsung Galaxy Tab S9, Pixel Tablet, Surface Pro 9.
- Laptops: 1280x720, 1366x768, 1440x900, 1536x864, 1600x900, 1920x1080 (FHD), MacBook Pro 14", MacBook Pro 16", 2560x1440.
- Desktops: HD, Full HD, 2K QHD, 4K UHD, 5K Retina, Ultrawide (3440x1440, 2560x1080).

• Realistic Hardware Chassis & Clean Viewport Mode
Inspect designs inside realistic device shells featuring punch-hole cameras, Dynamic Island, speaker slits, and laptop hinges, or switch to Clean Preview mode to isolate raw viewport pixels.

• Orientation Switching Without Reloads
Instantly toggle between Portrait and Landscape with one click or keyboard shortcut (R) without reloading the page.

• Multi-Device Comparison (Compare Mode)
Compare 2 to 6 devices simultaneously in a responsive grid with synchronized URL navigation and individual controls.

• Breakpoint Testing Bar
Instant one-click testing for 17 standard CSS breakpoints (320px to 3840px) with real-time category detection (Mobile, Tablet, Laptop, Desktop, Ultrawide).

• Independent Preview Zoom
Smooth zoom scaling (25% to 200%, Fit to screen, Fit width, 100%) that scales the preview viewport without modifying your browser's global zoom.

• Developer Overlays & Simulation
- Touch simulation with finger pointer and click ripple effects.
- Safe-area insets overlay (notch, status bar, and home indicator).
- Mobile browser chrome simulation (status bar, omnibox, and bottom bar).
- High-resolution measurement rulers.
- Accessibility helpers: Grayscale contrast mode and minimum touch target visualizer.

• Custom Devices
Create, edit, duplicate, favorite, and delete custom device dimensions with custom DPR and User-Agent hints, stored locally.

• Local Development Support
Seamless testing for localhost:3000, localhost:5173, localhost:8000, 127.0.0.1, and local IP addresses.

PRIVACY & SECURITY:
- 100% Client-Side: Runs entirely in your browser without telemetry or tracking.
- Local Storage Only: All preferences, custom devices, and favorites remain in your browser's browser.storage.local.
- No remote script execution or third-party tracking.