Email marketing is a great choice for your marketing campaign. It is cost effective and trackable. You can actually monitor how many people open the email, how many people click the links in the email messages, how many people direct themselves to your website from the email, and so on.
Tracking conversion rates is a powerful tool to see exactly which aspects of your campaign worked and what did not work. For example, if a low number of people opened the email, then you should probably change up your subject line. If a high number of people clicked on your email, but did not click on any links in the email, then you should probably work on your creative. If a high number of people opened the email and linked to your website, but did not follow through with a purchase, then you may need to work on your website, pricing, product, or a variety of other elements.