I searched this community and couldn’t find anything about odt, I found a few odt viewers on F-Droid and Aurora when I searched ‘odt’, but the only editors for odt, were ironically the proprietary Google Documents and Microsoft Word.
Have you found anything else?
AndrOpen Office is an Android port of LibreOffice. It’s not on Fdroid, but Aurora has it. It works perfectly fine for me, although the UI is not android specific.