You do not have to get any extra licensing - as long as this is a win app.
Web apps deployed internal to your org are fine also, however web apps deployed external to your org do need additional licensing. Check with sales on that: 866-681-3435
http://www.sap.com/contactsap/directory/index.epx
Couple of things you need to be aware of though. Only SAP Crystal Reports, Developer Version for Visual Studio .NET is supported in VS 2013. Also, Express does not support plug-ins. Thus you cannot run the install exe and you will not get the CR designer incorporated into the VS IDE. The only way (totally unsupported) to work with CRVS in Express VS 2013 is to run the 32 bit MSI and then manually add CR references to your project... umm, I will not say anymore on this as we are in an unsupported territory.
- Ludek
Senior Support Engineer AGS Product Support, Global Support Center Canada
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