I would only leave a flash drive plugged in. I do this and have had no issues. I don't trust an IPod/phone being left plugged in.
"what I'm driving here...is an ending." Jeremy Clarkson
2014 Whiteout Toyota GT-86 6mt(Presently enjoying WAY more than anticipated)
2011 Alpine White BMW M3 6mt ZCP Coupe(forced retirement 06/06/14)
2008 Alpine White BMW 328i 6mt Coupe(retired 06/21/11)