Free Mobile Performance Testing with Akamai's Mobitest
Test your website performance on a mobile device
Mobile Emulators and Simulators - The ultimate guide to mobile developers | Breaking the Mobile Web
Links to all the available mobile emulators!
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
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