WpSubscribers Plugin: All-In-One Popup and Opt-in Forms
Building an email list is not an easy job,
so every little bit of help is good.
In case of the WPSubscribers plugin
whose review you are reading right now,
not only does it help technically by collecting
the emails but it helps with some pretty unique
features you can use to increase the number of subscribers.
This plugin is all in one when it comes to building a list.
The lower end price makes it even better.
If you had to pick only one list building plugin, I would recommend this one.