Master of Many Styles, a monk archetype, has a class ability called Fuse Styles:
The master of many styles can have two style feat stances active at once. Starting a stance provided by a style feat is still a swift action, but when the master of many styles switches to another style feat, he can choose one style whose stance is already active to persist. He may only have two style feat stances active at a time.
The ability replaces Flurry of Blows, which is removed when the monk would wear armor. Thus the question: Can our master of many styles use armor and fuse styles at the same time?