Add Pixen (#1464)

README.md

@@ -569,6 +569,7 @@ Any comments, suggestions? [Let us know!](https://github.com/jaywcjlove/awesome-
 * [Paintbrush](http://paintbrush.sourceforge.net/) - Bitmap image editor. [![Open-Source Software][OSS Icon]](https://sourceforge.net/projects/paintbrush/files/) ![Freeware][Freeware Icon]
 * [Pencil2D](https://www.pencil2d.org) - A easy, intuitive tool to make 2D hand-drawn animations. [![Open-Source Software][OSS Icon]](https://github.com/pencil2d/pencil) ![Freeware][Freeware Icon]
 * [Pixelmator](http://www.pixelmator.com/mac/) - Full-featured image editor for Mac.
+* [Pixen](https://pixenapp.com/mac/) - Native pixel art and animation editor for Mac.
 * [Principle](http://principleformac.com/) -  Application for designing animated and interactive user interfaces.
 * [ScreenToLayers](https://github.com/duyquoc/ScreenToLayers) - Easily export your screen into a layered PSD file. [![Open-Source Software][OSS Icon]](https://github.com/duyquoc/ScreenToLayers) ![Freeware][Freeware Icon] [![App Store][app-store Icon]](https://itunes.apple.com/app/screentolayers/id1077317077)
 * [Sketch](http://www.sketchapp.com/) - Professional digital design for mac.