Meet Onyx: a smart gadget that pairs with iPhone and Android devices via Bluetooth and serves as a smart walkie talkie with unlimited channels. You will be able to send voice messages to other units over any distance. The device can be worn on your pants, shirts, and as a neckless.
Onyx is lightweight and compact. It lets you stay in touch with people that matter to you no matter how far away they are. Costs under $250 at this time.