Zinio didn't waste any time making its magazine store available on the newly-released Kindle Fire, bolstering Amazon's library of content with over 5,000 titles. Available publications range from Rolling Stone to The Economist, though we don't expect the majority of those to offer an experience tailored to the Fire's 7-inch screen. Most Zinio titles on other devices (including the iPad, TouchPad, and more conventional Android tablets) are strictly page-to-screen conversions, and can feel a little cramped even on larger displays. If you're okay with that, the app is available now on the Amazon Appstore for Android, and there's even a free $25 credit for new registrants that can be used against any magazine purchases.