MQtest.io — A simple tool to help identify which media queries your device responds to.
Public
Free Mobile Performance Testing with Akamai's Mobitest
Test your website performance on a mobile device
min-device-pixel-ratio test
What’s your device’s min-device-pixel-ratio?
This Is Responsive | Tips, Resources and Patterns for Responsive Web Design
Patterns, resources and news for creating responsive web experiences
Screenqueri.es | Pixel Perfect Responsive Design Testing Tool
Sweet