ExpoExe

An editable, fixed position div that sticks to the bottom of web page on mobile devices. 
Options for links and icons are editable under the Settings tab in WordPress Admin.

Mobile Only Contact Footer

An editable, fixed position div that sticks to the bottom of web page on mobile devices.

Maxaud

This plugin allows you to define different CSS rules that get loaded into the page’s for specific devices.
Includes checks for 18 different tablet options and 13 different phone options.
This can be useful if you need to target specific phones or tablets to make CSS changes or show certain advertisements for certain devices.
For more options or if you feel like donating, check out the <a href="http://codecanyon.net/item/mobile-css-pro/3182318/" title="Mobile CSS Pro" rel="nofollow ugc">PRO version of Mobile CSS</a> that is available for purchase.

Mobile CSS

Allows you to define different CSS styles that get loaded for specific mobile devices.

Mobile Only Contact Footer vs Mobile CSS