Flyers for the uninformed.
If I see a dude walking by wearing philips shp250 or something like that i always have an urge to say to him/her "man, these really suck". But urges are for dogs and horses and other animals to follow. We, the People, have objectives.
So instead of telling directly and avoiding kicks and punches afterwards we could give such poor uninformed music-lovers a cool, colour- and youthful flyer that says:
"Man, your phones really suck big...