Hybrid APP for work allocation for medical warehouse workers

Imagine a medical warehouse with "X" desktop computers and "Y" workers. The workers will have "M" apple phones and N android phones. Whenever an order from each desktop is approved and sent to the Server as a .json file, the Server should allocate the work to the worker who is free or has done a lesser work compared to the other workers. Basically the server should balance the work load and evenly distribute the orders amongst the workers for them to pack. The diagram below should give you an overall picture. This is fairly a very simple and straight forward project.