One way is to modify the HTTProvider so that it only outputs the data you want, in which case you could provide a querystring with app name to filter on. See this post for how to parse querystring:
http://community.wowza.com/t/-/245
Another way is to take the whole output and use an xml parser to extract. Here is a couple of user post that explore that with php.
http://community.wowza.com/t/-/34374#3
Richard