Hello,
i would suggest you to get your application implemented as a web-application, sort of a responsive webpage - of course a shiny nice looking one.
Creating a respnsive web application could ensure that the interface is gonna look the same well on different devices (from laptop through tablets to mobile devices).
For the logical back-end i'd suggest you to get a central data layer implemented, that'd be a web-server application organizing the communication amongst palyers and game master, recording chat history, etc..