Some articles and discussions to read regarding performance of Angular apps
Optimizing AngularJS: 1200ms to 35ms
http://blog.scalyr.com/2013/10/31/angularjs-1200ms-to-35ms/
Bind-once directive
https://github.com/Pasvaz/bindonce
Expression Namespaces
https://github.com/angular/angular.js/issues/6354 (read also the discussion below the readme)