What is an OPK package?

You told me if I can send my app to the QA as an OPK package, in order to test it.
What is an OPK package and how create it?

OPK is just a zip package of your main OW app folder, that allow you double click installation.

In order to create it, just zip your main folder of your app (where the manifest file is located), and rename it from ZIP extension to OPK.