I have been messing with the Mapfactor Navigator app on my Galaxy S5. I took it on the Concours and was surprised how well it worked. including (cover your ears) on the fly route changes, it worked much better than the portable Garmin I have in the car. And the touch screen works fine with ordinary leather gloves. zoom in, out, scroll, with a pinch of the fingers. It uses tom tom data and was completely free although they have a paid "better tom tom maps" lane preference etc. option.
What's really cool (and a bit scary) is it notices recent email and even google searches from my laptop computer and quickly fills in addresses after just a couple of letters/ numbers are entered!
The Mapfactor navigator allows me to download the map data to an SD card, no cell signal needed! With the Ulysse dash board app which also overlays the GPS map with gauges, I could get rid of most of the MC gauges!
Here's only one example of the near endless ways it can be configured.
Also has an accelerometer, you can do performance comparisons, trip meters, speed alerts and who knows how many other cool toys.
The charger I used was weak and the phone battery was slowly draining, even while charging but will try it with a better charger tomorrow.
Still working on phone mount options but near the left grip seems optimal.
Next up is finding a nice in ear blue tooth instead of a helmet blue tooth. I think it may allow the "holy grail" of voice address searches etc.
Get off the bike, pocket the phone and walk away.