Latex scanned Onyx Boox Note 3

I have a lot of scanned book in vrious formats : PDF, EPUB, DJVU like the ones you can retrieve at these links :

and I am looking at Boox e-link product to read/annote these books.

I would like to know if I can perform the following actions with these kind of files :

It is said that for instance the pdf is reflowable, but how does it technology for this kind of documents ?
Does it consider like a DVU/PDF image with no possible to select text or perform a matching pattern ?
Is is possible to access Glossary (typically at the end of the files) easily for instance by opening a second instance of the same file ?
can I install any kind of Android application, for instance the Seafile Android app ?
Do you see a better product for this (being e-link and allow the user to install non proprietary apps) ?

Thanks

Comments