Mathematica is not a replacement for Visual Studio (or XCode on Mac/iOS). If you need to develop a 'shrink-wrapped' app that a client can launch like any other app, you need other tools.
You can call the Wolfram Language APIs from within any c/c++, etc. application. If you need the Wolfram languages computational engine, this is an attractive solution. There are licensing costs associated with using Mathematica in one of its many variants.
Depending on your needs, you could use CDF player. The free player has limitations that may prevent you from using this solution. However, there are options for Enterprise versions or Player Pro that will let you do pretty much anything. Licensing these products costs less than full Mathematica, so this might be an attractive solution.
For many years I worked as an in-house developer/designer. I did all the R&D using Mathematica, but translated the results into a native c application. However, I did the bulk of the work with early versions of Mathematica (1-5), and I believe that I could rewrite the application using Mathematica 10 at far lower cost. (I have since retired, and will not get the chance to test this belief.)
Wolfram Research's marketing people can give you some idea of the solutions they sell, and you can see if it is a good fit. I have seen examples of real-time reporting, etc., that may be similar to what you have in mind. In my experience, using Wolfram Language instead of c or c++ can result in faster development, more flexibility, and a significantly smaller code base. The savings involved in these technologies should more than outweigh the licensing costs.
Hope this helps....