Let’s say you want to deploy an application to your clients but the vendor has removed all the downloads from their site and moved all the content to the Mac App Store. Most probably you would like to avoid the hassle of dealing with signed app on client computers. This is one of the cases where Wireshark comes in handy.
Many developers use(d) the great Sparkle framework to give their applications the ability of self-updating. So if you still have an old copy somewhere then fire that up, let Wireshark see what is going on and look for the
This is the case for example of Evernote. To get your Evernote copy free of Apple receipts get the zip file referenced in http://update.evernote.com/public/ENMac/EvernoteMacUpdate.xml
If you find more of these links please post a comment.