From the Store description:
After the success on Windows Phone, Traffic lands on Windows 10 as a Universal App! Checking the traffic in your city has never been easier!
HIGHLIGHTING ON TRAFFIC IN 23 COUNTRIES!
Traffic jams, accidents, interruptions for road work will not be a surprise anymore, check Traffic before leaving, and plan a better itinerary
(USA, Canada, Italy, France, England, Germany, Spain, Brazil, Portugal, Switzerland, Austria, Belgium, Denmark, Netherlands, Scotland, Ireland, Greece, Finland, Norway, Sweden, Poland, Luxembourg, South Africa - coverage will always be increased).
REAL-TIME TRAFFIC ALL OVER THE WORLD
You can quickly check the status of real-time traffic in your city in a very simple way from any device: mobile phone, tablet or PC.
CORTANA LOVES TRAFFIC
"Traffic around me", "Traffic New York", "Traffic Boston" etc., use these simple commands and get access to the app directly from Cortana!
Use the Search function to check the traffic in a particular street
SAVE YOUR FAVORITE ZONE
You can save your favorite areas in Cloud to check the situation from all of your devices.
All isn't quite what it seems, mind you. For starters, there's the mystery of why this application is 50MB when all its data is sourced from elsewhere. Then there's the Cortana integration - this didn't work for me at all on either phone or PC. The Google traffic link-up didn't work on PC, so no colour coded roads. Finally, despite being a UWP application, there was no Continuum compatibility (which I found odd).
Having said all that, the basics did work on my Windows 10 Mobile phone (a 950 XL in this case):
With its data sourced from at least three different places, Traffic is at risk from things breaking on a regular basis, and this isn't helped by the oddities and inconsistencies within the app's code itself. Still, it's not without utility - and comments welcome if you use it regularly. Does it surface genuinely useful information that Windows 10 Maps or Waze couldn't tell you?
You can grab this here in the Store - it's free with ads, or there's an IAP of £3 or so to remove these. Yes, this is relatively expensive as mobile apps go (maybe the TomTom traffic feed has to be licensed?), but if you find its data aggregations useful each day then this won't be an issue?