Android Internet not connecting

I have a simple method that is attempting to connect to the internet.
It works in the Unity editor and in a standalone build, however it doesn’t on Android.

public static IEnumerator Login(string username, string password, Action complete)
{
	WWW reader;

	do
	{
		string url = string.Format(UrlStart + "Login.php?user={0}&pass={1}", username, password);
		reader = new WWW(url);
		yield return reader;
	}
	while (reader.error != null);

	Logger.Log(LogTopic.Framework, "Logged in as " + username);
	complete();
}

As you can see there’s not a lot to it, yet for some reason it doesn’t work.
I made sure internet is a requirement in the player settings, my phone’s internet is turned on. I even manually typed in the URL on my phone (in the browser), and I got the results I expected.

What would cause this?

I didn’t have ‘http://’ in the URL. This meant it didn’t work on Android.