Answer: Basically create a dummy new ASP.NET Web application. Change the debug browser menu and run the app. Close the dummy app. Open your SharePoint 2013 App and you should have your browser changed.
I don’t know why there is no better way to set default browser for the SharePoint 2013 for debugging.
The following link is the source for the content:
http://www.lifeonplanetgroove.com/set-default-browser-for-debugging-sharepoint-2013-apps/