Seems like a really useful idea and great execution too. I've never used the real punch cards in action before, may be I'm not aware of it. But this is something that I would definitely love to use!
Never used real punchcards?? That's impressive... something like ~94% of Americans have them laying around. Whenever I pitch Punchd to a group of people they all have punchcards and they all always forget them at home.
That's a fun idea, but we'd destroy your battery polling the gps. The best we can do is put up some fancy posters so you remember when you're standing in line :)
