Ask HN: How do you remember things you think of while walking?

Pulling out my cell phone and opening an app isn't good enough (fumble for the phone, enter PIN once, maybe twice, load the app) and I'm really not good at walking while using a pen and paper. In particular, if I'm walking with my girlfriend or friends I want to record the thought but not really interrupt the flow of conversation. I've considered digital voice recorders, but would prefer something easier to get to. If my Pebble could record audio, that would probably be the "best" solution to me.