MailChimp recently launched Mandrill, its new transactional email product, and I stumbled across some interesting results while dogfooding it with a couple of side-projects. For those of you who don’t know, transactional emails are just one-off emails triggered by some action like signing up for an account or requesting a password reset.
Some back story: by day, Drew and I work in MailChimp’s Mobile Lab. In our spare time, we run a little company called R7, and we make a few financial related iPhone apps (BillMinder, and its lesser-known sibling, DebtMinder). Whenever new users downloaded those apps and created accounts, we used Mandrill to send their welcome emails. This post is about how we used Mandrill’s beautiful reporting tools, as well as some design tweaks to our welcome email, to increase unit sales of one of the apps by 57%.