HTML5 apps will also be able to incorporate Amazon's Javascript-based in-app purchasing API, to better monetize their products. You can learn more about the web app support expansion here.
Developers can now submit URLs for their HTML5 web apps and mobile websites and have Amazon offer that content to millions of Kindle Fire and Amazon Appstore customers in the same, convenient way as native apps.
Amazon opens app store to HTML5 developers
Amazon announced today that it is expanding its existing app distribution platform to accommodate HTML5 apps on Kindle Fire and Amazon's app store. "We're giving web developers the tools they need."