vinmatrix

Sometimes we need to have more fileds for WordPress administrator,Lets us take an example, we have only 
one admin mail setting in wordpress, and if we need more than one then we need to have an interface to maintain 
other email ids. Like this we can maintain N number of custom fileds dynamically through this WP Admin Custom files plugin.

WP Admin Custom Fields

Allows to maintain N number of Custom fields dynamically for site administrator.

rightmessage

RightMessage helps online businesses grow their list faster and generate more sales through survey funnels and personalized calls-to-action (CTAs).
This plugin makes it easier for those of us who use WordPress, by:
<ul>
<li>automatically installing your RightMessage snippet into your WordPress site</li>
<li>giving you segmentation options in your RightMessage account like “Current Post” and “Visitor’s Favorite Category”</li>
<li>giving you shortcodes for inserting embedded forms and trigger links for opening other kinds of forms</li>
<li>automatically appending a personalized opt-in form at the bottom of all your blog posts, if you want</li>
</ul>
<h3>Privacy</h3>
This plugin relies on the third-party service RightMessage to integrate personalized calls-to-action into your website. Data is sent to RightMessage when the plugin is activated and configured. For more information, please review <a href="https://rightmessage.com/privacy" rel="nofollow ugc">RightMessage’s Privacy Policy</a> and <a href="https://rightmessage.com/terms" rel="nofollow ugc">Terms of Service</a>.

WP Admin Custom Fields vs RightMessage WP