Yesware
Yesware is a small business CRM software that will help you measure, track and maximize sales outreach with convenient tools featured inside your inbox. Their email tracking tools will let you know who's opening your links, attachments and messages in real-time. Using this software will enable you to create email templates, so you don't have to spend your valuable time rewriting your most used messages. This CRM software also allows you to add a reminder to the emails you consider important and want to remember to follow-up at a later time. The emails tagged will then come back to the beginning of your inbox when specified.