Nomad Programmer

<p>It will help you to make only one logged in at a time on WordPress sites. if user wants to log in two or other places than it will destroy all other sessions.</p>
<p>This Plugin uses function like WordPress 4.1, that have a button on the user profile screen which clears all other sessions, and on the user editing screen which clears all sessions. This plug-in can limit simultaneous login. This plugin use for every user automatically.</p>
<h3>Licence</h3>
<p><a href="https://wordpress.org/about/gpl/" rel="ugc">GNU General Public License</a></p>


One Active session

Working till now

This plugin clears all other logged in sessions and allow only one login by one user

ericjuden

<p>This plugin allows you to use $_COOKIE, $_SERVER, $_SESSION, $_GET, $_POST and $_REQUEST data in a Gravity Form through the merge tags of a field. I’ve only really tested this using a hidden field.</p>


Gravity Forms Extended Merge Tags

It's amazing how few people seem to know about this plugin. Incredibly simple, but also really helpful when using $_SESSION variables to track website visitors.
I use it to get referring website data, so I can easily store it in a $__SESSION variable. Then when the visitor fills out a Gravity Form, I can pass along the stored vars.
I crafted a Lead Source Tracking for Salesforce script that uses this plugin to pass along the details to Salesforce when a form is submitted.



Brilliantly simple

This plugin allows you to use $_COOKIE, $_SERVER, $_SESSION, $_GET, $_POST and $_REQUEST data in a Gravity Form through the merge tags of a field.

One Active session vs Gravity Forms Extended Merge Tags