I am currently looking at OpenXchange (OX App Suite) as alternative or extend my NextCloud to fullfil the groupware job (with missing of ActiveSync which is really a pain for me).
Does anyone of you have a history with both options?
ActiveSync is not nessesary for us, CalDAV and imap are working great. OX ist written in Java and Java sucks :) and the “webmailer” from nextcloud is lousy.
I will try to patch the 5 user licence from gromox/grommunio - it should be open source.