Email tracking plugin

Hi everyone,

My company requires a way to track email conversations that we have with our customers. We are building a new WordPress site where — ideally — customers would send us an inquiry through a contact form, and we would be able to track our conversations with them directly through the Dashboard.

My question is: What are the best plugins available that would allow us to do this? The closest thing we know of with this functionality is Venuebook, but we would like to have this functionality as part of our website. (Think of it as sort of an all-in-one package.)

Thanks!