Hi Michał,
1.) Hmm depends, there are two forms for adding events in the frontend. One more or less simple one (where you also can set who is allowed to do what and you can have multiple menu entries for it too).
And there is also an advanced form, allowing to manage even more. Basically thought for organizers with logins in the frontend.
matukio.compojoom.com/submit-event
2. Is it possible to sell tickets for events?
Can you explain a bit more? Matukio has a ticket functionality, including QR Code generation and check-in.
3. Is it possible to create some kind of page about users with informations about them. Some bussines card.
You can have organizer detail pages.
4. Is it possible to create calendars with all events from one user?
Calendar files yes, calendars in sense of the calendar view not. You can have event listings with events only by one user.
Kind regards,
Yves