[Test]
public async void GetProfileTest ()
{
    var profileFragment = new ProfileFragment();
    var result = await profileFragment.GetProfileAsync();

    Assert.IsNotNull (result);
}

//#define TEST // Uncomment this to start UnitTestig

 . . .

 [ /* Your ActivityAttributes */ ]
 public class YourLauncherActivity : Activity {

      protected override void OnCreate(Bundle savedInstanceState)
      {
           base.OnCreate(savedInstanceState);
    #if (DEBUG && TEST)
           // Your TestConfiguration.cs Activity
           Intent iTestConfiguration = new Intent(this, typeof(TestConfiguration));
           StartActivity(iTestConfiguration);
    #endif
    #if !TEST
           // Run your normal Activity here, like Login, etc...
    #endif
            }
        }

    ...

[Activity(Label = "TestConfiguration")]
    public class TestConfiguration : Xunit.Runners.UI.RunnerActivity
    {
        //public static Context Context { get; set; }

        protected override void OnCreate(Bundle bundle)
        {
            // tests can be inside the main assembly
            AddTestAssembly(Assembly.GetExecutingAssembly());
            AddExecutionAssembly(typeof(ExtensibilityPointFactory).Assembly);
            // or in any reference assemblies
            //this.AutoStart = true;
            base.OnCreate(bundle);
            //Context = this;
        }
    }

public class MyTests
    {

        public MyTests()
        {
            // Before each test
        }


        [Fact]
        public void FailingTest()
        {
            Assert.True(false);
        }
    }

. . .
        public static TestSuiteInstrumentation CurrentInstrumentation { get; set; }

        public TestInstrumentation(IntPtr handle, JniHandleOwnership transfer) : base(handle, transfer)
        {
            CurrentInstrumentation = this;
        }
. . .

[TestFixture]
    public class LoginTests
    {
        private TestSuiteInstrumentation instrument = TestInstrumentation.CurrentInstrumentation;
        private Activity CurrentActivity;

        [SetUp]
        public void SetUp()
        {
            Instrumentation.ActivityMonitor monitor = instrument.AddMonitor($"{instrument.TargetContext.PackageName}." + nameof(Login), null, false);

            Intent intent = new Intent();
            intent.AddFlags(ActivityFlags.NewTask);
            intent.SetClassName(instrument.TargetContext, $"{instrument.TargetContext.PackageName}." + nameof(Login));

            Task.Run(() => instrument.StartActivitySync(intent)).GetAwaiter();

            Activity currentActivity = instrument.WaitForMonitor(monitor);

        }

        [Test]
        public void LoginTest()
        {
            // Verify your activity is not null
            Assert.NotNull(CurrentActivity);

            // Convert CurrentActivity to your Activity
            Login login = CurrentActivity as Login;


            // Verify your views are not null, finding views in your Activity
            Assert.NotNull(login);
            Assert.NotNull(login.FindViewById<EditText>(Resource.Id.etLoginUsername));
            Assert.NotNull(login.FindViewById<EditText>(Resource.Id.etLoginPassword));


            instrument.RunOnMainSync(() => {

                // Here you can run your UI methods for Views, example
                login.FindViewById<EditText>(Resource.Id.etLoginUsername).Text = "hello";
                login.FindViewById<EditText>(Resource.Id.etLoginPassword).Text = "world";
            });

            // Here will be your assertions
        }
    }

[Activity( ... , Name ="com.yourpackage.android.Login", ...)]