Contact form 7: Contact Form 7 can manage multiple contact forms, plus you can customize the form and the mail contents flexibly with simple markup. The form supports Ajax-powered submitting, CAPTCHA, Akismet spam filtering and so on.
 

Campaign Monitor: Create stunning e-mail marketing campaigns. Design engaging email marketing campaigns with simple drag-and-drop tools. Your design is guaranteed to look amazing in every inbox, on every device.
 

Mailchimp: Built for growing businesses. You don't need to be a design or tech whiz to use MailChimp. Their design tools make it easy to create sophisticated campaigns that shine a light on the best of your business. Send 12,000 emails to 2,000 subscribers for free.
 

ManyContactsBar: Install a tiny script on your web site and automagically receive enriched visitor information. As soon as an email address has been filled in your form, our magic script collects the email, even if the form is abandoned. Then our servers enrich information about your new lead. It also works on shopping cart, landing page, signup forms or live chat widgets. Your lead's information is sent by email.
 

iContact: If you’ve played around with other email marketing platforms before, iContact will hands-down be your favorite — and not just because you can call, email, or chat with our support team when you have a question. Building an email doesn’t have to take days — with iContact, it takes minutes.
 

Hello Bar: Convert visitors into customers with Hello Bar.  98% of visitors leave your web site without taking action. 
 

Delivra:  Send personalized email campaigns that increase sales and engage patrons. Smarter email automation, data warehouse for segmentation, track your KPI's and ROI.
 

Sumome List Builder: List Builder converts one-time visitors into lifelong readers and customers. Create professional-looking pop-ups that appear on clicks, timers and before people leave! With advanced drag-and-drop functionality, this is the most advanced (yet easiest to use) email capture tool on the internet.
 

Active Campaign: Build email newsletters. Create campaigns. Send great emails to stay in front of your audience—and offer exactly what they want to see.
 

Scroll Triggered Box: Boost your conversion rates — Wordpress only.
 

Drip: Understand your customers, build real relationships, and sell like a human for humans. You’ll outlearn, outlove, and outsell your competition with the world’s first ECRM.