SwiftNinjaPro

This plugin blocks non-admin users from using inspect element, while still allowing access those with manage_options permission. 
The plugin also blocks some of the common keys(f12, ect.) and optionally can block right-clicks for non-admin users. 
Admins are unaffected by the plugin entirely. This plugin is also able to block users who open developer tools on another site, before visiting your site.
Version 3.0 update
This plugin is now fast and accurate, and should work on most browsers. 
This plugin can detect the browser console based on lag increased by opening the console. This detection is tough for a browser to prevent or get around. 
The detection runs fast, and has some resistance to lag spikes.
Lag detection does mean your site needs to have ok performance, but when testing it, I could play 10 of 10 youtube videos all at once without a false positive. 
During my tests, detection was still within the second I open dev tools, and successful if I go to the page with it already open. 
I tested this in chrome, firefox, and chromium. 
I also tested this on my somewhat slow website with tons of wordpress plugins installed (and the 10 videos at once test) without false positives.

Developer Tools Blocker

This plugin blocks non-admin users from using inspect element, while still allowing access those with manage_options permission.

Angry Creative

ac-robin

Sammy Nordström

The Angry Creative Inspector, or Angry Inspector for short, will weigh, measure and find possible issues with your WordPress installation. This plugin is especially recommended to maintainers of WordPress installations that needs to continously monitor the health of their sites. Got WP-CLI? Then you may even be able to repair what’s wrong with your WordPress. Read on to learn more.
The inspector has two basic types of inspection routines; regularly repeating inspections run once every 24 hours and inspections triggered by a WordPress hook or user action. Currently, the following regularly running inspection routines are supported out of the box:
<ul>
<li>File permissions check – You didn’t do a chmod 777 on all files, right?</li>
<li>Git modifications check – Is your WordPress revisioned by Git? Then we log uncomitted file changes.</li>
<li>Database collation check – Does your tables have the proper character set and collations?</li>
<li>Site visibility check – Is your website blocking search engines?</li>
</ul>
Then there’s the following WordPress hook or otherwise user action triggered routines:
<ul>
<li>Plugin enabling/disabling – Who disabled or enabled that plugin?</li>
<li>User registrations – Logs all user registrations. No more, no less.</li>
<li>User profile updates – Logs all user profile updates, even password changes.</li>
<li>User capabilitiy changes – Who promoted or demoted that user?</li>
<li>Site registrations – Who created that site in your site network?</li>
<li>Site enabling/disabling – Who disabled or enabled that site in your site network?</li>
<li>Javascript error logging – Keep track of javascript errors, even the ones that appears in your visitor’s browsers.</li>
</ul>
A little configuration is needed to take full advantage of the file permissions and site visibility routines, see installation instructions.
<h4>Doing inspections and viewing inspection logs</h4>
Login to your WordPress site with an administrator account and navigate to the Angry Inspector page under the ‘Settings/AC Inspector’ menu in the WP admin panel (in network admin if multisite). In here you should see the inspection log and may trigger the scheduled inspection routines manually by clicking the “Inspect now” button. Also take note of the “Inspection routines” and “Action routines” tabs where you among other things may change the log level for each routine. Set log level to ‘ignore’ to completely disable a routine.
<h4>Inspect and repair using WP-CLI</h4>
First make sure you have WP-CLI installed, see http://wp-cli.org for instructions. Then navigate your commandline shell to your WordPress install directory and issue the following command:
<pre><code>wp angry-inspector inspect
</code></pre>
You may also call a specific inspection routine like this (use all lowercase name of class or function without “ACI_Routine_”-prefix and replace underscores with dashes):
<pre><code>wp angry-inspector inspect file-permissions
</code></pre>
Any inspection remarks while inspecting with WP-CLI will cause the inspector to look for a possible repair method and prompt you with the question wether you would like to make an attempt at repairing if one is found. Want to skip inspection and go directly for repairing? Here’s how:
<pre><code>wp angry-inspector repair
</code></pre>
To call a repair method for a specific inspection routine:
<pre><code>wp angry-inspector repair site-visibility
</code></pre>
Please note that for utilizing a repair method like the one for file permissions, you need to run the command as super-user (root) and add –allow-root to your WP-CLI commands, like this:
<pre><code>sudo wp angry-inspector repair file-permissions --allow-root
</code></pre>
That’s all there is to it, really. Note that the given log_level option is just a default and may be overridden in the ‘Settings/AC Inspector’ menu in the WP admin panel (in network admin if multisite) like all the other registered inspection routines.
<h4>Creating your own inspection routines</h4>
Are you skilled in the arts of WordPress development and have a need for a check not covered by the above? Then you should extend the inspector with your own inspection routine! It’s really simple. Here’s an example you can put in your theme’s functions.php or in a plugin (after plugins loaded):
<pre><code>if ( function_exists( 'aci_register_routine' ) ) {

 $options = array( 'description' => 'My awesome inspection routine!',
 'log_level' => 'warning' ); // Possible values: notice, warning, fatal, ignore

 $action = 'ac_inspection'; // Default inspection action run once every 24 hrs

 aci_register_routine( 'my_inspection_routine', $options, $action );

 function my_inspection_routine() {

 $inspection_passed = false;

 // Put your inspection code here,
 // then log your results like so:

 if ( !$inspection_passed ) {
 AC_Inspector::log( 'Your WordPress-install did not pass your inspection routine.', __FUNCTION__ );
 }

 // No need to return anything...
 return;

 }

}
</code></pre>
For a bit more advanced developers, you may also register a class as an inspection routine. The syntax and function used is the same, it’s just a matter of passing the class name instead of a function name. The inspector will by default look for a class function called ‘inspect’ to register as inspection method, otherwise you may add ‘inspection_method’ => ‘your_inspection_function’ to the options array to use any class function you like as your inspection method.
The reason why you would want to register a class instead of just a function is that it gives you the ability to extend the settings for your routine beyond just the log level and maybe even add a repair method to call if the inspection fails (WP-CLI only).
First off, here’s how you extend the settings for your routine (inside your inspection routine class):
<pre><code>public static function settings_field( $options, $args = array() ) {

 $routine = $args["routine"];

 /**
 *
 * Input field name convention: aci_options[<?php echo $routine; ?>][field_name]
 * Input field id convention: aci_options_<?php echo $routine; ?>_field_name 
 *
 **/

 ?>

 <tr valign="top">
 <td scope="row" valign="top" style="vertical-align: top;">Example setting field</td>
 <td>
 Here be extra settings field :)
 </td>
 </tr>

 <?php

}

public static function settings( $options ) {

 // Here be code that parses and validates submitted values

 return $options;

}
</code></pre>
Then when you register your routine:
<pre><code>$default_options = array( 'log_level' => 'warning',
 'description' => 'My awesome inspection routine!' );

aci_register_routine( 'my_inspection_routine_class', $default_options );

// Optional extra settings fields
add_action( 'my_inspection_routine_class_settings_field', array( 'my_inspection_routine_class', 'settings_field' ), 10, 2 );
add_filter( 'my_inspection_routine_class_settings', array( 'my_inspection_routine_class', 'settings' ), 10, 1 );
</code></pre>
Your extra settings fields should now be visible in either the Inspection or the Action routines tab under the ‘Settings/AC Inspector’ menu in the WP admin panel (in network admin if multisite).
For a complete example routine class, checkout the routines/wp_mail.php file in the plugin directory.
As for registering a repair function, it works the same as when registering a class with an inspection method. The inspector looks for a class function called ‘repair’ by default. Override with any class function you like by defining ‘repair_method’ => ‘your_repair_function’ in the options array. However, a repair method will never be called automatically. You need WP-CLI ( http://wp-cli.org/ ) installed and issue the appropriate commands, see “Inspect and repair using WP-CLI” above.
Happy… no wait, angry inspecting! 🙂

Angry Creative Inspector

Inspects, logs and with the aid of WP-CLI, it may even repair possible issues with your WordPress installation.

Developer Tools Blocker vs Angry Creative Inspector