Appium 1.6.4 desktop browser web app testing on real Android Samsung Galaxy tablet


I have some Python test cases, which test web apps in browsers, that work on Android and iOS simulators with the Appium 1.6.4 desktop server running.

I am trying to have these tests run on a real physical Android Samsung Galaxy tablet, with a USB cable connected. When I try to do so, the browser opens, but the web page does not load.

I have these following properties in a configuration file to load into the desired_capabilities dictionary for this physical device:
platformName = Android
platformVersion = 4.2.2
deviceName = GT-P5113
browserName = Browser

What am I missing?