followit

s-feeds

This plugin allows an “automatic” newsletter which means: You publish a post (as usual), and then we send out a notification to all your newsletter subscribers. That way they get to know about your new post, and come back to your website (increasing your traffic)!
It’s very easy to set up. Simply install the newsletter plugin and place a subscription form (and subscription icons) on your website.
Then people can subscribe to your newsletter and receive notifications by:
<ul>
<li>Email (either one email per day or a single email for every published post)</li>
<li>RSS</li>
<li>News site</li>
<li>Telegram</li>
<li>Coming soon: WhatsApp, Browser push notifications and other delivery channels!</li>
</ul>
For example, have a look at <a href="https://www.follow.it/techcrunch2?subParam=followPub" rel="nofollow ugc">this sample subscription page</a>. You can link to such a subscription page with a “follow” icon on your website.
As you can see there, your newsletter subscribers have many options to specify which updates they want to receive, and how. Providing your visitors with more newsletter options means more subscribers for you!
The plugin is powered by the newsletter service <a href="http://follow.it" rel="nofollow ugc">follow.it</a>.
The service can be used both in conjunction with, or as alternative to, mailing services like Mailchimp, Mailpoet, Aweber, Convertkit, Tinyletter, Sendinblue and many other email service providers.
To get access to your newsletter subscribers, please “claim” your feed. You can do that directly in the plugin (third step).
The newsletter service is FREE no matter how many subscribers you have (on the basic plan). Check out the (optional) <a href="http://follow.it/features-and-pricing" rel="nofollow ugc">Premium Features</a>.

Newsletter

What a cool plugin ;-) 
(Full disclosure: I'm the plugin creator)



Does what it's supposed to do

The Online Outbox plugin allows you to easily add a subscription form to your WordPress site, to grow your list of email subscribers of your Email Newsletters, Mass Email Marketing messages, Email Autoresponders, Email Surveys, Optin Emails, Email Marketing Statistics.
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.
Requires an account at www.OnlineOutbox.com. Accounts sending fewer than 500 emails per month are free.

Online Outbox Subscription Form

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