Mobile projects can be defined as either Native, Web or Browser. It is important to distinguish which one of these is required before creating visual direction. I like to explain it this way:
An application built in a platform specific technology (e.g. Objective C, Java).
These apps are provisioned via an app store, marketplace or upload server, and do not require a web browser or HTML layer to function.
A set of functions in a paginated architecture built with a low pay-load and a focus on non-transactional features. More like a mini web site.