Company C has N employees.
Employees can work on different shifts at different sites.
Every day a supervisor has to call employees and instruct them on the shift/site for the following day.
Every employee has been given a company cell phone with a Vodafone SIM.
Calls between company cell phones are free.
We were asked to write a phone application.
The app will drive a sort of cell modem.
The coder will suggest the best hw solution.
The voice quality is important here.
The modem command strings will be read from an INI file (so to quickly replace a broken modem with a new different modem).
The coder will provide a library that exposes a list of commands (see the attachment)