Simple Subscribe started as discomfort with all the subscription plugins out there. I wanted to have a plugin that just works, and let's me control the output if I need it to. And since none of the others do that, or require you to pay for additional features, I've decided to make my own.
It is the only bulletproof subscription plugin, that is easy to use and developers friendly as well. It gives you the power to simply add subscription form to your WordPress website, as a widget, shortcode or using php in your templates.
Subscription form can gather more than just e-mail address tho, you can select additional fields like name, location, age and interests. All the subscribers can be exported into .csv, .xls, .tsv or .xml format and used anywhere else, in fact, you can even select to export by criteria active, or inactive or simply all.
All the outgoing e-mails can be customised, and you can e-mail your subscribers directly.
There is plenty of other features you can check out on plugin's site here.
Important Update: Since version 184.108.40.206 the plugin has been acquired by dabelon and I have nothing to do with the next development (Readygraph etc.) and how plugin behaves. It has been a great learning experience for me and I would like to thank all of the users up until the point of acquisition for their patience and support.