No, your app can be written in any language and hosted by any web server running on any OS. HttpVPN Proxy, however, at this time has to run on Windows. Since HttpVPN Proxy talks to applications it hosts over standard HTTP or HTTPS, it can reach multiple different machines inside the same LAN.
Support of redistributable web applications at this point is limited to those running on Windows, but
manually-registered non-redistirbutable web apps can run on Apache under Linux, or whatever else.
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