Guys, thank you very much for the "One-Click Apps" category, however would be great to expand it with other yet not well-known apps.
My suggestion is OnlyOffice - free cross-platform groupware: https://www.onlyoffice.com/open-source.aspx
Great app! I use only online editors (called ONLYOFFICE Document Server) with my Nextcloud to co-author docs with my team.
But it seems that this link is out of date. I have found the information on their new site .org
It would be great to add it, now it provides not only with a set of collaboration tools but also with online editors and mail server.
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