Apks on Inkpad 3 Pro?

Hi. I was looking for the diccionaries directory in my Pocketbook and found an strange folder with anbox (for those that don't know, it's like an compatibility utility for android apps on linux) and a lot of .apk files, in the disk/system/priv-app folder.

So, I've got a question in my mind: Is possible to add other APKs than the ones that have come with the system itself?

Best regards