After months of trying to determine the perfect time to leave the office to get home, I've come to the disappointing conclusion that it doesn't exist. Sometimes leaving at 5:41 allows me to sail home relatively traffic-free, other days I'll sit for an hour at 5 MPH, never knowing for sure if that "sweet spot" was 10 minutes behind me, or if I just missed it by a couple minutes.
I see that Waze data is used to alert Google Now users to traffic problems in advance, without them asking (http://www.techradar.com/us/news/phone- ... ze-1236657). That should mean that Waze knows my preferred route. Couldn't the same knowledge be used to monitor that route and send me a push notification (or the Android equivalent for the Android users) when it's time to leave in order to get the best possible speed home? I'm thinking a notification on my phone that pops up and says, "Speed on [highway name] is now up to 50 MPH" at which point I know it's worth leaving the office and getting in my car. Ideally, I could set the threshold speed, so if I'm willing to sit in traffic moving at 30 MPH and someone else isn't, we would each be notified at the speed we are willing to travel.
Obviously there will be multiple data points along a route... you could average them but that would still leave you with unhappy people in the event that it's really slow at one end and really fast at the other. Basing it on the lowest speed along the route seems best. I know Waze can do this, because when I enter a destination it shows my whole trip with slow areas in the middle of the progress bar. This would essentially be just watching that same progress bar view actively and then alerting the user when it matches an acceptable condition.