What good online project and event management softwares are

[elvina]

I am looking for a project management software that has a task manager function, calendar and that's preferably customizable to my organisations needs. Ideally, I would like such a software to have an event management function also.

Is there anything like this online? This could be something that is pay monthly (or yearly) or a one off purchase.
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construction management | project management | quality assurance