While the previous version of HERE Maps for iOS was built around HTML5, the new release is a completely native app, designed for iOS 7 and iOS 8. The new app also features an offline mode, allowing you to save maps to your device, according to the official HERE 360 blog:

You can save maps to your phone so that the whole HERE app can be put into 'offline mode' and it won't use any data. Even if your iPhone is in flight mode, you can still see where you are, search for places and navigate there on foot, by public transport or by car.

Offline car navigation features full turn-by-turn audio support, including spoken street names, for both driving and walking. HERE Maps also lets you save destinations ahead of times with Collections, and you can create and view your collections on iOS, Android, Windows, and the web.

HERE Maps is rolling out on the App Store right now, though you may have trouble downloading the app due to the extended iTunes Store outage.

Source: HERE