Breadcrumb is a new startup that makes Bluetooth-enabled nocks and homing beacons. Insert a Breadcrumb into an arrow like any after-market illuminate nock, and when fired, the 41-grain package emits a “beep,” flashes blue light, and sends a tracking signal to your smartphone. It can be picked up wirelessly from 50 yards away or better. You can share that signal with other smartphones and theoretically the whole deer camp can help find your blood trail, or that vanished 10-point.