Yes, you could call PowerServer's Web APIs, but those Web APIs are generated for a PB client so it's returning the entire DW result set with DW buffer info. The best practice approach would be to open up the generated C# code for the Web APIs in SnapDevelop and scaffold your own services and controllers using the non-PB Client template. It would reuse the same DataWindows in the PowerServer project... so all you doing is creating the API interface, which if you just want a standard interface SnapDevelop does automatically for you. So then all you need to do in terms of manual coding is add user authentication.