Passur uses active radar and restricts access to its' apps outside US AFAIK. Flightaware.com uses FAA feed (with a slight delay), but thus has full coverage of

Passur uses active radar and restricts access to its' apps outside US AFAIK. Flightaware.com uses FAA feed (with a slight delay), but thus has full coverage of US airspace and a lot of other useful information (flight plans etc), but its' map sucks.