As I said, the final design will largely depend upon the service model and requirements. For instance, if your app requires user to be connected to internet to be able to use it... then it might as well serve better to have a web app. Its not possible to comment which one will serve better w/o knowing what functionality they are going to have. Biggest Adv of HTML5 app is a uniform code-base and you will not have to worry (about user upgrades) when adding/upgrading to new features. A native app allows you to store information locally which can be retrieved easily in offline mode. HTML5, with local storage, does allow data storage... but that may not be as much as native app (I'm not very sure about data storage details as I haven't used them for HTML5 app)
Imagination is the one weapon in the war against reality!!! http://aniruddhaloya.blogspot.com