Do the devices allow bi-directional messaging? What information can be sent from the device and what information / commands can be received by the device?

Bi-directional messaging is not supported; however, RiskBand ARIES devices can receive action messages for the purpose of providing users with urgent information (e.g., active shooter notifications).  Devices can send periodic GPS data when not in an emergency state and may also send emergency requests as a result of man down or impact/fall events, or as a result of pressing the emergency button on the device, which includes photos captured, GPS data, and 2-way audio communications.