I used Review19 -- http://review19.com http://review19.com (Disclaimer: this is my app) for collaborative project tracking and that covers my consulting work an

I used Review19 -- http://review19.com http://review19.com (Disclaimer: this is my app) for collaborative project tracking and that covers my consulting work and personal projects. I've used Trello and Google Docs in the past and they work great as well.