TimeSite Pro - TimeSite Pro is a fully configurable, cloud-based time tracking, expense & invoicing solution.
Paws for Trello - The best way to use Trello on your desktop
TimeSolv - Legal Time Tracking & Billing Software.
Elegantt for Trello - The most elegant way to manage your Trello projects
WiseTime - Web-based automatic time tracking software
TunnelVision - See your next Trello tasks every time you open a browser tab