There are many ways to improve online collaboration within your team. Most importantly, if you are using Microsoft Outlook to send emails, schedule appointments and keep track of your everyday tasks, then you probably would find it useful to be able to synchronize Outlook. You can synchronize many things in Outlook, e.g. sync Outlook calendar, share Outlook calendar with others and so on.
Synchronize Outlook between your workmates and you will improve groupwork within your team immediately.