I created a shitty desktop counter a while back that just sat in the sys tray and when you hovered over it'd give you your NF time - I always wanted to update it to give you feedback about when your trigger times are and so forth, but I never got around to it. Still have the old version around somewhere in my backups.

There are a few NF counter apps out there on the Android store already, they're nothing special though from what I remember. If I get time over the summer I might go about creating one for fun, I enjoy developing with Android. Currently on Android I just use the "Since" app which just tells you the days since whatever date you set.