Stefano Lissa

This simple and little plugin integrates the <a href="https://wordpress.org/plugins/popup-maker/" rel="ugc">Popup Maker</a> plugin with forms 
of <a href="https://wordpress.org/plugins/newsletter/" rel="ugc">Newsletter</a> plugin, usually generated via 
shortcodes. It follows the Popup Maker standard integration methods.
Note: this plugin should be considered as developed indipendently from Newsletter and Popup Maker. For support, contribution and so on 
use the support area provided by wordpress.org. Much appreciated.
<h4>Other Newsletter plugin integrations</h4>
<ul>
<li><a href="https://wordpress.org/plugins/newsletter-buddypress" rel="ugc">BuddyPress</a></li>
</ul>

Popup Maker Addon for Newsletter

Adds support to Popup Maker for Newsletter subscription forms

Paloma

The Paloma Widget is a plugin developed by Paloma that allows administrators of WordPress websites to collect newsletter subscriptions from their visitors. To do this, the WordPress user must first have an account on the Paloma website and an address list where the new subscriptions should be added.
The widget currently only accepts a subscription if it has a name and a valid e-mail. The admin can also select up to three optional fields for the subscription in the widget menu.

Paloma Widget

This widget allows the user to capture Paloma newsletter subscriptions from visitors and send them to an address list in their account.

Popup Maker Addon for Newsletter vs Paloma Widget