There are advantages and disadvantages to having apps vs browser. We feel average phones and tablets already have too many apps, and users don't want another app to install and uninstall. Also, we have to consider that an average person keeps his/her phone for about 2 years. When he/she sells the phone, they don't delete the app at all, and that could be a liability. Besides, with the advance of browser technology, we're seeing a shift from native app to browser based app right now.
Having said that, we don't rule out developing an app. We'll do so when the situation dictates.