OK, I have a dedicated GPS unit, but My smartphone with google navigation is much better in the city. Google updates road construction delays, and such. So when I'm on My C14, I like the phone for in town navigation, and also, the battery on the phone lasts 10 times longer. That is more convenient, as I don't have to fiddle with plugging it in.
The main issue, is smartphones don't work with gloves on. There are capacitive gloves for sale on ebay, and they look useless for protecting Your hands against road rash, and they sell conductive thread on the net for about a billion dollars a spool.
Here is where being a pack rat comes in handy. I ripped the stranded wire out of a cheap pair of broken earbud headphones, and untwisted it. The result is a strand of wire about like a human hair. It is plenty good enough to do this job. Take a sewing needle, and thread the wire, 8 or 10 loops through the fingertip of Your riding glove, and then You can use Your phone GPS or music player, no problem.
Cost, an hour sitting at the kitchen table, and being way too close to the delicious donuts in the box on the counter.
Hope this helps. Mac