Some of music's biggest names gathered today to announce the relaunch of Jay Z's streaming service, Tidal. BeyonceMadonna, Nicki Minaj, Jack White, Daft Punk, Arcade Fire, Alicia Keys and Rihanna were just a few of the musicians to step forward and sign their names in support of the artist-owned service. Here's what you need to know about Tidal. 

1. It's priced at $9.99 and $19.99. Unlike with Spotify, Tidal does not offer a free version of its service. You can tune in at $9.99 for its premium version, or $19.99 for lossless music - CD quality sound. 

2. You can try it for free for 30 days. Tidal currenty offers a 30-day free trial, so if you're not sure you want to take the plunge, you can give it a spin. 

3. It's artist-owned. Jay Z, Kanye West, Jack White, Deadmau5, Daft Punk and Usher count themselves as owners of Tidal. The idea of the company is to fairly compensate artists - more so than other streaming services like Spotify. 

4. You can use one device in online mode and up to three devices in offline mode at once. Spotify Premium has the same rules for simultaneous use across devices. 

5. You can stream Taylor Swift. T-Swift broke the hearts of her fans when she declined to release her album on Spotify. Swift is on board with Tidal, though, so big fans may need to take this into consideration.