Hot on the heels of rival Pandora’s IPO yesterday, Slacker Radio has its own offering for the public: Slacker Premium radio for its iPad app. The app brings all three levels of Slacker service to the iPad – Slacker Basic Radio, the ad-free Slacker Radio Plus, and now, Slacker Premium, which offers music on-demand.

Of course, listening to music on the iPad app isn’t too different from listening to music on Slacker’s iPhone app, but the iPad’s larger screen definitely makes browsing through artist bios, album reviews, artist pics and album art a much more pleasant experience.

A new feature also made its way onto both the iPad and iPhone versions of the app. From now on, you’ll be able to create Pandora-esque custom stations by choosing multiple songs or artists. Plus, Slacker promises to bring ESPN Radio content to the mix soon. The Slacker Radio iPad app is available now as a free download from the Apple App Store.