I've found that Skala Preview is also a very solid app for live previewing. Somewhat different to others, it integrates with Photoshop for live retina previews.

I've found that Skala Preview is also a very solid app for live previewing. Somewhat different to others, it integrates with Photoshop for live retina previews. I've no association, its just a great app. http://bjango.com/mac/skalapreview/ http://bjango.com/mac/skalapreview/