Now you can use Navionics charts with the iNavX marine navigation app. The iNavX in-app chart store is the only independent navigation app to offer Navionics charts. Currently available through the AppStore for iOS only, iNavX provides full-featured navigation on iPhones and iPads, even when no cell service is available. The app uses built-in GPS as backup in case main navigation system fails.
Price: $19.99 for iNavX app, charts start at $24.99