pandoraSoundHound, a music discovery app for iPhone, is announcing the release of version 3.1 today. The release includes updates that make the app respond more quickly on launch, as well as integration with Pandora and the addition of tour information.

SoundHound, like the better-known Shazam, is built around the core functionality of tune identification — holding up your iPhone to a radio and being told the name of the song and artist. You can also sing or hum into the phone and get back song matches, or just say the name of a song or artist to pull up info on each. In addition, SoundHound links to your iTunes library, lets you buy matched tunes at the iTunes store, and offers artist bios, song lyrics, and related YouTube videos.

All these features were available with version 3.0. Today’s update lets you launch a station on popular Internet radio service/iPhone app Pandora based on the matched song, as well as providing upcoming tour dates for popular artists.

Like the music search site, SoundHound is the creation of Melodis. Both services are powered by Melodis’ Sound2Sound Search Science technology. In fact, SoundHound was known as Midomi Ultra until Melodis launched the SoundHound brand in December. On, users can actually contribute their own renditions of songs by visiting the Midomi “Studio.” According to the site, these homemade recordings are a key component of Sound2Sound matching technology. The Sound2Sound algorithm matches the singing or humming of the searcher with sung renditions by other users. Presumably SoundHound taps the same data sources.

Early iterations of the Midomi mobile app had some stability problems and a skimpier set of features, but SoundHound 3.1 sounds like a much more fully realized application.

Melodis is funded by Global Catalyst Partners, TransLink Capital, Walden Venture Capital, and JAIC America. Larry Marcus of Walden is on the board of directors for both Melodis and Pandora.