Code96

This plugin easily detects mobile devices and redirects them to the mobile version of your site. This plugin also gives you the ability to bypass the mobile redirect based upon a cookie that is set on your mobile site. This allows you to redirect mobile users and give the option to “View Full Site.”
If you are upgrading you must enable the redirect via Settings > PHP Redirect
To set the cookie simply add the following PHP code to your mobile site:
setcookie(“mobile”,”m”, time()+3600, “/”);
The mobile redirect bypass cookie is optional, and should only be used to give your users a “View Full Site” option
Code 96 offers <a href="http://www.code96wd.com" rel="nofollow ugc">WordPress Design</a> services and custom <a href="http://www.code96wd.com/premium-wordpress-themes/" rel="nofollow ugc">WordPress Themes</a>.

PHP Mobile Redirect

Easily detect mobile devices and redirect them to the mobile version of your site.

Joe Rhoney

average.technology

<blockquote>
Notice 
 Average is changing its name to AddFunc (thank goodness). Therefore, this plugin has been republished as <a href="https://wordpress.org/plugins/addfunc-mobile-detect/" rel="ugc">AddFunc Mobile Detect</a>. The “AddFunc version” is compatible with the “Average version,” so installation and activation is risk-free. This also enables you to manually transfer all of your redirects to the “AddFunc version” if you’re going to switch to it (although some values will automatically carry over from the “Average version”). Keeping both versions running simultaneously after transferring your redirects however, is not recommended. The “Average version” will remain available with minimal support until it becomes a burden for AddFunc (probably for many years to come, as of 2014). Any new features will only be added to the “AddFunc version,” so it is of course the recommended version (at least moving forward). Thanks!
</blockquote>
Uses <a href="http://mobiledetect.net/" rel="nofollow ugc">Mobile Detect</a> to redirect mobile traffic to your mobile website.
<ul>
<li>
Redirects on a page-by-page basis (posts and custom post types included). For example; <code>yourwebsite.com/contact/</code> will redirect mobile devices to <code>yourmobilewebsite.com/contact/</code> instead of always redirecting to your mobile home page.
</li>
<li>
This can be overridden on any page individually with a convenient meta box adjacent to the WYSIWYG (usually underneath, by default).
</li>
<li>
Sets a cookie to remember which version of your website (desktop or mobile, usually) your visitors opted for (so it’s okay to set a link on your mobile site to view the desktop version).
</li>
<li>
Includes a widget for inserting a link back to your mobile site, which is only generated for mobile devices.
</li>
<li>
Includes two shortcodes for generating links to your mobile site. One is generated only for mobile devices and the other is generated regardless.
</li>
<li>
No CSS rules are used and classes are provided, yielding coders full reign to style generated links to fit the website theme. Shortcodes even allow you to set the link’s classes.
</li>
<li>
Adds a class to the <code><body></code> (“<code>mobile-detected</code>“) to help coders write styles specifically for mobile devices.
</li>
<li>
Leaves 404 errors untouched, allowing you to maintain 404 statuses.
</li>
</ul>
Basically, it gives you loads of control of your mobile redirects.
Custom support tickets are available
See <a href="https://wordpress.org/plugins/average-mobile-detect/other_notes/" rel="ugc">Other Notes</a> tab for details.
<h3>Custom Support</h3>
If you have a custom support need, <a href="https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=7AF7P3TFKQ2C2" rel="nofollow ugc">please purchase your support ticket here</a>. Support tickets are responded to within 24 hours, but we answer them as soon as possible.
How it works
<ol>
<li><a href="https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=7AF7P3TFKQ2C2" rel="nofollow ugc">Purchase a support ticket via PayPal</a></li>
<li>You get a chance to provide the best way to contact you and a description of your need</li>
<li>I contact you as soon as I can (no less than 24 hours) and help resolve your issue</li>
</ol>
Note: This is for custom needs for help, not problems with the plugin, or instructions that should already be explain in the description. If you feel there are important details omitted from the description, installation steps, etc. of the plugin, please report them in the Support forum. Thanks!

Average Mobile Detect

Redirects mobile traffic to mobile site, allows visitors to opt for desktop site, provides shortcodes and widget to generate links to mobile site

PHP Mobile Redirect vs Average Mobile Detect