There are a lot of email tracking tools out there, but I really, really love the user interface of FollowUp.cc. It's a great tool to use in Gmail and I like being able to track all emails. Review collected by and hosted on G2.com.
I used to get it for free, now there is a cost. That is really all that I dislike. I haven't run into any problems, and the user interface is super easy to use. Review collected by and hosted on G2.com.
