Grrr. Android's Bluetooth filesharing deliberately restricts to specific MIME types.
So I can't Bluetooth share an ePub (which is just a ZIP file) without first renaming it to .zip.
I can't install QuickShare on the receiving Android device (generic eInk tablet with no Google Play).
There are no FOSS QuickShare apps that I can find.
Is the only solution installing yet-another sharing app on all my devices?