HTML5 is often touted as the best alternative to developing platform-specific apps, but options for selling HTML5-based apps are somewhat thin on the ground. Amazon is looking to change that by adding the option for developers to sell HTML5 apps via its app store.
One of Amazon's key motivations is to increase the base of apps for its Android-based Kindle Fire device. While that isn't sold in Australia, local customers finally got access to the Amazon app store itself back in May, so it's still a good opportunity even if your app is mainly aimed at Australian buyers. More information at the Amazon developer site link below.