Doesnt even show up in Open in... for zip files

I downloaded a zip file in Safari and was trying to open it in this app. Unfortunately this app doesnt appear in the list of available apps when I tap the Open in... option. This omission seems like a very basic feature that users would want, meaning viewing zip files downloaded from the web.

Im uninstalling this app.

Tony.T about My Document - File Manager for PDF, Video, Office