This question deals with teamwork and emails. I'm facing the following scenario.

I have inquiries and other important mail sent to a shared email address. All 4 team meambers have full access to this email. I'm using a googlemail to manage that email address. 

There's a huge load of emails coming to that inbox: inquiries, orders, requests... The team has to deal with messages, reply and take actions accordingly. However the problem is... ok while I can use IMAP to let each member have their email clients synchronized (Android, Apple Mail, Thunderbird...), how to alert other members in the group? Specifically, how to make aware the rest of the team members when one of the team members has answered to a message? And also, even if one of the members does not answers... but only reads an incoming new message, the message will be marked as read and other members could not notice it. 

So the question is... how to synchronize teamwork in a way everyone is informed of other people actions in regards of receiving/sending email? This could work with CC/BCC but I do not really wish to do that, seems more confusing. 

Are there any solutions (possibly free/open) for this situation? I'd wish to use googlemail as email provider in any case and people should be able to check everything both from web, desktop clients and mobile clients. Perhaps this could be addressed with a ticket system... Any advices?

thanks!

---

*[This might not be a programming related question but I'm not sure which stackexchange site should I use. If some mod thinks it's unappropriate to post here, please direct me to the appropriate site and then delete the question. Thanks ]*