Hi Cecilia,
- if you want to leverage PowerBuilder only for server-side processing (data connection and data handling), you can use the datastore object and deploy the entire data model 1) right now (PB 2017 R2) as SAOP/XML .NET Web Services or .NET Assemblies or 2) as C# Web-based middle tier (aka C# Web API, but must wait for PowerBuilder 2018).
- If you also want to deploy the presentation tier in PowerBuilder, you can use Appeon PowerServer Web, which converts an entire desktop application to a n-tier .NET/JEE Web application, with additional Desktop Web Application built-in feature (via the IWA option).
In essence, if you are willing to try asap, I would encourage you to give a try to Appeon PowerServer Web and IWA.
If you want to wait the next major version, C# Web API and Desktop Cloud Apps will be the new rocking features.
Marco