Would be extremly helpful to pass a location string link "Prinzipalmarkt Münster" to a mapping service like Google Maps or similar.
Maybe the service could be selectable / configurable on a config sheet /Page.

Events of other users should be shown side by side. That would be way more easy and overseeable than one upen the other.
I would be very thankful in you added this feature.

Every time I send invitations to others and they do anything with it (decline or accept) I get an email as notification. In our team meanwhile are a lot of emails every day, we don't need to have. An option to opt it out, that you get notified about anything would be nice! Maybe distinct between several notification options

I have a shared contacts list with tens of thousands of contacts, all with birthdays. It would be nice if I could opt out of syncing birthdays to my phone, so that I wouldn't get daily alerts about them.

When you invite someone, would be nice to upload logo and stuff, the invitation mail looks personalized though. Or in another words: invitation mails with your own corporate design!

I share team shares with my team. When I call delegation from someone, I also see all the team shares, again. So I have it always double the times I someone delegated to me and see all the entries multiple. Would be nice you can define, these team shares are not visible by definition. Not to opt them out via interface

Maintain a single list of contacts with sync specification.
In each contact, you can specify to which devices it will be synced.
Sync with my phone, not my wife, not my sister.
Sync with my phone, not my wife, with my sister.
Just for those who have (almost) no secrets for their wife :-p

Allow fruux and zoho calendar synchronization

When you add an account, you dont have time to specify in your phone how to make the sync, eg. one way sync, web to phone.
Which uploads 'garbages'

To be able to have online the same settings/display that you have on your mobile

It would be awesome to synchronise two CalDav / CardDAV Server to each other for e.g. families that use different kind of email providers but want to have the same calender/contact data.

A different colour for college activities, society meetings, family gatherings, etc.

Currently it will show that an attendee exists, but you can't change them or add new people to the list to send a notification.

Please - can you do something so that when a user accepts a meeting invitation in Outlook on their Mac it gets added to their Fruux calendar? If Microsoft won't play nice with others, maybe others can play nice with Microsoft? We are a small organization, all on Macs, no exchange server.

On the web interface the addresses books are on the left, each with a different color. But the contacts, listed in the middle of the page, have color(s) which do not match which address book they are listed in. So I need to open each contact, one at a time, to figure that out. Thanks.

Give an option to set the alarm for the night before the event.

Often I want to be reminded before I go to bed so I can plan my day.

In chinese, we use the order like "Last Name" "First Name".

When sharing calendars, all events get shared with their notifications. In my eyes it does not make sense to get notifications for a read-only calendar of my colleague. It'd be nice to disable the notifications on a calendar base.

In the web calendar, allow users to change month by scrolling. It would be then faster to browse the calendar, when you do not need to click the small buttons.