Can the attendees use the app if there is no Internet connection?
Yes. Attendees will still be able to view everything on the app; as far as the agenda, logistics, attendees profiles, sponsor banners, etc.
However, the app does require internet connection in order to use the networking features like sending in-app messages and interacting via Twitter, as well as taking the surveys and receiving push notifications.
Whova is a native app, along with Facebook, Twitter, and other social media apps, where this circumstance is common.