You might also look at the geocaching community. They might make for some great partners to get the word out about your startup's use & potential to a slice of

You might also look at the geocaching community. They might make for some great partners to get the word out about your startup's use & potential to a slice of your target market. Probably just need to coordinate some event(s) and donate/lend some of your hardware and you could find some loyal fans. Not sure if it'd work out or be worth it, of course, but an idea.