Their handled version of the home page doesn't mention any charge, but the regular page has a notation of $0.50 application download fee.

http://www.telusmobility.com/on/wweb/navigator.shtml

It is confusing as well which phone/pda it can work on. My HTC Touch is not in the list, but the FAQ says any phone/pda with the location sign would work. And the last thing from the FAQ,

"
Am I using data when I use the navigation service?

No. All of the data required for navigation is included the monthly or daily subscription.
"