I do this rarely since I rarely ride in a city or other urban environment but I have used the routing this way a few times- I usually take someones Strava route and then save it to my Strava account. Then, I use my Garmin 1030 to follow the route. It will show you where all the turns are and if you are following the right line/route. The last time I tried this was on an unfamiliar mountain route last year. I never use my phone for routing or cycling. I prefer Garmin computers since I am used to them and I love the larger screen of the 1030 Plus. I can see it much better when riding than the smaller screens most have.