Email is one of the most-used communication tools, which makes it one of the hardest to maintain. Inbox Checkup from the makers of the Front email app analyses your Gmail inbox and provides a report on your habits.
The service can tell you how often you reply to emails, how many emails you send, how much you actually reply to the email you receive (which may be a good indicator of how much junk you're getting), and your average response time. It won't help manage the email you actually receive, but if you want to get a top-down view on your email habits, it's a handy tool.
Inbox Checkup [Front]