This is an incomplete list of the most popular email auto-responder services available.
Some I’ve used, some I haven’t, some I am using currently. But it’s only in the list because I believe that the service is top quality, either through direct use, or from recommendations from my trusted friends.
I’ll be expanding this to a more comprehensive comparison of the important features of each of the services in the future. Look out for posts with in-depth reviews of each as well, as time permits.