Garrett Grimm

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Creates a ‘Coming Soon’ page that will show for all users who are not logged in. Useful for developing a site on a live server, without the world being able to see it

underConstruction

Came across this plugin because I forgot to put a space in between 'under' and 'construction' never looked back, so easy, so simple just gets the job done!

Just does it!

Creates a 'Coming Soon' page that will show for all users who are not logged in

Fugu Design

One-click maintenance mode
This plugin adds a button to the admin bar for toggling the builtin maintenance mode.
Core maintenance mode
A .maintenance file is generated and copied to the WordPress installation folder when turning on the maintenance mode. 
A maintenance.php file is generated and added to the wp-content folder for custom HTML code.
Your custom maintenance page will also be active during the core, plugins and themes updates.
<h4>Special Features</h4>
<ul>
<li>
set which roles can switch the maintenance mode
</li>
<li>
set which roles can bypass the maintenance mode on the frontend
</li>
<li>
set the entire HTML code used for the maintenance page
</li>
<li>
preview the maintenance page before saving
</li>
<li>
enable the theme file support, so you can create in each your themes a maintenance.php file to customize the maintenance page
</li>
<li>
restore all default settings
</li>
<li>
restore default HTML code
</li>
<li>
create/delete the maintenance file in the active WP theme
</li>
</ul>
<h3>Translations</h3>
<ul>
<li>English – default, always included</li>
<li>French</li>
</ul>

Maintenance Switch

Customize easily and switch in one-click to (native) maintenance mode from your backend or frontend.

underConstruction vs Maintenance Switch