Aspects of an auto injector device are provided which allow for increased reusability, portability and convenience, thermal insulation, and safety. The auto injector device is encapsulated in a case for a mobile communications device and includes a cartridge, an outer casing fixed to the case and attached to the cartridge and including a piston, and a sensor attached to the case. The cartridge is configured to contain a fluid and includes a needle. The piston is configured to pump the fluid in the cartridge through the needle in response to application of a force during injection of the auto injector device. The cartridge is detachable from the outer casing. The sensor is in wireless communication with an emergency alert system, and the sensor is configured to sense movement of the needle and to communicate with the emergency alert system in response to application of the force during the injection.
