MobileTest.me – Mobile emulation to test your mobile sites and web applications right from your browser.

iPadPeek.com – iPad & iPhone simulator to quickly check your content on an iPad and iPhone from within the browser.

ProtoFluid – Effortless responsive design testing. This application gives you a form to enter your URL – which can be a local URL – and view the design as if in the browser on an iPhone, iPad or a range of other devices.