Star Walk 2 (US$2.99 with in-app purchases) is a solid update from the original award winning Star Walk astronomy program. This new version has a re-designed interface with the look and feel of each element beautifully crafted and drawing you into the inner workings of the app.
One of the horizon views contains a lake -- the water looks realistic and the reflection of the stars and planets sparkle, giving a tranquil feel.
Animation seems smoother in this version, and I particularly liked the 3D views of some objects. a a example, Messier 33 -- a galaxy relatively near to us -- can be rotated on screen and viewed from any angle. You can also do this with many comets, man-made satellites, and even constellations.
The augmented reality view remains as a holdover from the original app. Orient your iPhone or iPad toward the sky and the app activates your camera so you can see charted objects appear superimposed on live sky objects. It's a great way to explore the night skies.
You can scroll a list of objects visible on any night and from any location on earth. Tapping on an object name displays popups that give you information on the object, a Wikipedia link for more details, and a 3D option if there is one for that item. It's all very smooth and worked without problems.
The app also contains a soundtrack and specific sounds for specific controls, but I found them irritating and turned them all off. If I'm outside, I'd rather hear the crickets.
Star Walk 2 is universal this time around, so one purchase allows you to load it on any iDevice. The downside is that some content that was free in the original Star Walk is now an in-app purchase. Satellites, comets, a deep sky objects are now part of an extra pack. All the extra content bundled is an additional $1.99. I would have much rather seen a small price increase from version 1 that covered the extra features, which most people will want anyway, than in-app purchases.
Some features from Star Walk are missing, like an event calendar and views through a finder scope. The developers say an imminent update will return the missing features.
Star Walk 2 is an impressively good looking app, but it's a bit thin on data unless you buy the add on packages. The original Star Walk app remains in the app store, and if you have it and upgrade I'd keep the old version around until all the features it contains migrate to Star Walk 2.
Star Walk 2 requires iOS 7. It runs on any Apple iDevice as noted, but I liked it most on my iPad for the extra size and readability. Star Walk 2 is a terrific introduction to astronomy for young and old. It's also handy for serious stargazers for observing planning.