Design a Smart Wristband PCB

We're looking for an electrical engineer to assist us in prototyping a smart wristband for the purpose of parents communicating with their children. The Use Case scenario is: "A family goes to a Water Amusement Park and the parents and kids leave their phones within the lockers. The parents need to communicate with their kids for simple needs like meeting for lunch, returning to the lockers, indicating an emergency and monitoring the geo-location of family members." The Bracelets would pair with an App we're developing via BTLE to register as part of a network. The App will be configured in a manner to monitor the location of the Bracelets, receive phone alerts when Bracelets go out of a pre-set radius and allow triggering of alerts to the Bracelets. The Bracelets would communicate via a cellular SIM module which would provide location services (via GPS) and data connectivity. The Bracelets would come in two varieties - a Master Bracelet and Slave Bracelets. The Master Bracelet would allow the parent to push one of two buttons (with both single-press and long-press capability) to trigger four alerts on the Slave Bracelets. These alerts could be done via an audible tone, however, it would be preferred that the Bracelets accommodate an acoustic speaker to produce recorded voice alerts. Finally, the PCB would then be manufactured with a waterproof silicone enclosure to allow Users to wear them at Water Amusement Parks. The PCB would require the following components: * Two Tactile Push Buttons * Processor * Buzzer • Or Preferably an Acoustic Speaker * BTLE * Cellular SIM • For Data Connectivity and GPS Location * BIOS and Flash Storage Memory • For Logging and Audio Files * Battery • Or Preferably a Rechargeable Lithium Ion Battery * Microphone * Waterproofing The selected Freelancer will both design the PCB and RnD components that would be cost-effective and meet the minimum functional requirements as stated above. Deliverables would be Gerber Files, Source Files and a BoM.