This isn't peer2peer, the RIAA can't see what you're doing unless they themselves are in control of the app and search engines. From what I can gather, the app searches known servers on the internet hosting the music, like how you can do the same thing by hacking google (intitle: etc) and isn't necessary illegal for the app makers if all they are doing is linking you to a search engine. That would make google illegal because you can use it for finding pirated things. If you live in the u.s. then yeah, it is illegal to download copyrighted material but not all record companies are under the RIAA's umbrella and won't go after you for doing it. In fact, Radiohead and NIN put their own music on filesharing networks and asked for donations and made more money than they would have through a RIAA connected record company. riaa radar is a good source for figuring out what acts are potentially risky.
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