There are multiple options for Autoresponders that you can use to send emails. Among those are: 

1. Prospect Rocket: 

Get Prospect Rocket here: 

2. Aweber 

3. Get Response 

4. Mailchimp

5. Infusionsoft  

6. iContact

You can also read this article to learn more about how you can integrate the different autoresponders mentioned above with Social Covers.

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