[Koha] iphone/android scanner apps?

has anyone thought of having iphone/andoid apps to act as bar-code scanners and handling infrastructure tasks (shelving, checkin, etc) I know I've heard of such apps that take pictures of the bar code, decode it and do various things with it, with the prevalence of such phones and the relative scarcity of dedicated bar-code scanners, it seems like having something like this would be handy. David Lang