WHAT IS THIS? Weird things in the tiapp.xml file that people comment but is UNDOCUMENTED

I'm trying to get my app to be "portrait only". There are many, many questions about how to do this - none of them work. But that's now what I am asking here!

Instead, I've noticed that a lot of answers have this kind of jazz:

<android:label="Mytest" android:name="MytestApplication"
        android:debuggable="false">
 
        <activity android:name=".MytestActivity"
            android:label="Mytest" android:theme="@style/Theme.Titanium"
            android:configChanges="keyboardHidden"
            android:screenOrientation="portrait">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

What is this Mytest/MytestApplication/MytestActivity crap? From a reading of the android manifest doco (found here: http://developer.android.com/guide/topics/manifest/activity-element.html) says that the name should refer to a class.

Also, i think not having an "edit" button for questions here is stupid.