Which class to use for display?

Which class should I use as the base of displaying a PDF inside a fragment?

I found, there are a couple of candidates and the JavaDocs are completely unclear which class does exactly what?

PDFView, PDFViewCurl, PDFLayoutView or PDFGridView?

PDFView is base class ith empty implement.
PDFViewCurl is derived class from PDFView.
these 2 classes used in Module PDFReader
PDFLayoutView used in Module RDPDFReader, which support very large zoom scales.

PDFGridView display first page of all pdf files under a path.

I see. I studied the PDFReaderAct in the demo.

So, I assume, to use the com.radaee.reader.PDFReader class, I need to import it as a module in Android Studio, the same way I did with ViewLib.
However, when I do this:
I change PDFReader Module to be a library instead of application, fix an issue with the manifest merger change the launch configuration to use my app's main activity, I am getting DUPLICATE app icons!

Please advice, how to fix that.

Fixed by removing
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
from PDFReader Manifest