Can i use the webviewer component this way?

Caution - I have never submitted an app to Google Play.

This board has a Google play FAQ at FAQ Section: Google Play Store

I am not a lawyer.

Even worse, I have not built a .jar file in years, and never a .dex file.

So regard my observation as a hunch from some one who has no skin in the game, that JavaScript is generally regardless as harmless.