I am not sure what you are looking for. Autodesk Freewheel and Project Freewheel allow users to upload DWF files. They are about as secure as email. In general no one will obtain an URL to one of your DWF files on Freewheel unless you send it to them. I don't envision this changing in the immediate future. I recognize that if you need something more secure, then a solution like Buzzsaw is more in order.
If you put anything accessible for Freewheel, other people can also see it using web spiders. Commercial apps can be defined "secure" only if the contents are encrypted, don't you think? That's also the reason that now, most email servers are using HTTPS by default. But yet, emails are considered insecure that people are requested not to send important information via Email, such as bank account, SSN, etc..
Our client would like to view DWF diagrams on their cellphone. I noticed that the DWF viewer is only available on iPhone, are you guys working on a DWF viewer on Android?
Now the only cross-platform solution is Freewheel. However, we also need our DWFs to be encrypted, meaning not anyone on the Internet can see it even if they have the link.
Let me know your thoughts. Thanks a lot.
Right now AutoCAD WS (http://www.autocadws.com) is getting the attention in terms of a sharing solution for drawings that is platform independent. The Labs team is working on Project Photofly (http://labs.autodesk.com/utilities/photo_scene_edi