Is this some sort of pirate TV station or IPTV channel?
No. All of the content for this app comes from The Internet Archive: a digital library of Internet sites and other cultural artifacts. Any content on this site can be found by going directly to the Internet Archive and searching their archive of shows. This site is simply a hand-curated list of shows organized by category.
Screenshot of the Internet Archive website
Television is an ephemeral medium. The Internet Archive began archiving television programs in late 2000, and their first public TV project was an archive of TV news surrounding the events of September 11, 2001. In 2009 they began to make selected U.S. television news broadcasts searchable by captions in their TV News Archive. This service allows researchers and the public to use television as a citable and sharable reference.
The Internet Archive serves millions of people each day and is one of the top 300 web sites in the world. A single copy of the Internet Archive library collection occupies 145+ Petabytes of server space (and they store at least 2 copies of everything). The Internet Archive is funded through donations, grants, and by providing web archiving and book digitization services for their partners. As with most libraries they value the privacy of their patrons, so they avoid keeping the IP (Internet Protocol) addresses of readers or viewers. The Internet Archive is a California non-profit charity that is tax-exempt under section 501c3 of the Internal Revenue Code.