Just open the extension manager inside of Brackets and copy the extension link (http://ionicbrackets.com/Ionic-Brackets-Extension.zip) into the extension url field and hit install.
Or you manually extract the zip file into your Brackets’ extension folder.
A: Currently, it gives you code hinting for most of the Ionic framework attributes and directives.
0.4.0 | 2015-07-11 | Added support for Ionic Analytics
0.3.1 | 2015-06-01 | Improved Angular hinting
0.3.0 | 2015-02-23 | Added support for AngularJS directives
0.2.0 | 2015-01-26 | Added two attributes for ion-content
0.1.0 | 2015-01-18 | Initial public release