Media Queries: Quick reference for the widths of the screens for the most popular devices http://premium.wpmudev.org/blog/responsive-design-css3/
Phone – 640px
iPad – 1024px
Tablets – 1366px
Android phones – 640px, 720px, 854px, 960px are the most typical sizes
Extra large android phones – 1024px or 1066px
Smaller Windows phones – 480px
Larger Windows phones – 768px
Smaller and older phones – 320px
Netbooks and small desktops – 128px
Ultrabooks/Laptops – 1366px
Desktops and TVs – 1920px