A Developer's Guide — The WordPress Theme Customizer - A Developer's Guide - http://wp.smashingmagazine.com/2013...
In case you missed it, WordPress release 3.4 included a very exciting new development: the Theme Customizer. This allows users to tweak theme settings using a WYSIWYG interface and customize the theme so it includes the colors, fonts, text — and pretty much anything else — they want. - disconnesso