This is actually on the features request for Mantano Reader. Not sure if they'll implement it or not but I believe it's under consideration.
That said, I think there are two options you can already accomplish this using Calibre:
- Use the Save to disk option. In Preferences, under Import/Export » Saving books to disk just make sure the Update metadata in saved copies option is enabled.
- Use the Sent to device option. In Preferences, under Import/Export » Sending books to devices select the Automatic management option in Metadata management.
Aldiko, Moon Reader, Cool Reader, FB Reader and Mantano Reader all seem to support reading metadata in epub files so either of the above should do the trick. Just remember to use the epub format when saving/converting your ebooks.