To say the universe is big would be a gross understatement, so the idea of creating an app that lets people explore outer space must be hugely intimidating. Solar System simulator Cosmographia tackles the subject on a limited scale, by focusing on just the stuff in our galaxy. It has 3D models and star maps, great visual effects, and everything is built from real scientific data.
Cosmographia is akin to a beginner’s guide to the Solar System, and insofar as that it’s an impressive app — well presented and pretty to look at, with no assumptions of prior knowledge. But it doesn’t go deep enough, and you’re likely to leave wanting more.