Top Producer - Real estate crm software.
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
Realty Pilot - Realty Pilot is a suite of paperless real estate software.
GoodGantt - The best Gantt chart for Trello®
Close - A CRM with built-in calling, SMS, and email
Paws for Trello - The best way to use Trello on your desktop