I'm looking for some ideas on a direction to take on a project. I have a software package that I want to develop. When I discussed the software with a potential customer, the first question I got was does it run on a mac? The second question was does it run on an iPad? The third question was how about the web? So, here is where I am looking for ideas. I'm thinking I need to write this as a client server package so the server side handles all the data and validation and the client is "dumb" and only handles the input and output and will be easier to write. I'm looking for suggestions on the data trasnfer mechanism. I'm thinking about using JSON but not sure that is the right direction. I'm also not sure how to do the connection between the client and server because I've not done anything with client / server. Does anyone have any good ideas and maybe knoow of a good website or book that I could use to learn how to write the connection parts?