I know, listening to music while cycling is a touchy subject. A lot has been said about it on the net (even some seriously overheated debates), but it's a common sight on the streets and bicycle lanes these days. And yes, I listen to music while cycling too. Mostly on my morning commute that is. At 3:30 am there's not much traffic about, and other road users can easily be seen by their lights. So the music isn't that much of a distraction. The only part of my morning commute where I turn the music off, is while riding through the woods. No music can beat the singing of the birds. ;)
From mechanical odometer and cycle computer to smartphone app. I’ve used it almost all. Nowadays I use both cycle computer and smartphone app. Cycle computer because I had it at hand (and while mounted on the bike it’s not just lying around), app because I like to look back at the rides I’ve been doing.