Both [SauceLabs][1] and [TestingBot][2] support manual and automated testing on real devices over the internet. You get a session to the device and can interact with it.

Also [BrowserStack][3] offers a similar service, but on virtualized devices. The other providers give the feelings its on real devices, but they could be virutalized too. This might also be something you could do yourself for free: http://developer.android.com/tools/devices/emulator.html

Also check the [Ripple Emulator][4] if your main focus is to test how your-sites look at different resolutions and mobile-browser features.


  [1]: https://saucelabs.com/features/#features-manual-testing
  [2]: https://testingbot.com/features/manual-browser-testing
  [3]: https://www.browserstack.com/
  [4]: https://chrome.google.com/webstore/detail/ripple-emulator-beta/geelfhphabnejjhdalkjhgipohgpdnoc?hl=en