Stellarium is described as 'free open source planetarium for your computer. It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope' and is a very popular Star Map in the Education & Reference category. There are more than 50 alternatives to Stellarium for a variety of platforms, including iPhone, iPad, Android, Windows and Android Tablet. The best alternative is Celestia, which is both free and Open Source. Other great apps like Stellarium are Sky Map (Free, Open Source), Space Engine (Paid), Gaia Sky (Free, Open Source) and KStars (Free, Open Source).
Celestia is an application for real-time 3D visualization of space, with a detailed model of the solar system, over 100,000 stars, more than 10,000 galaxies, and an extension mechanism for adding more objects.
Almost everyone thinks Celestia is a great alternative to Stellarium.
Space Engine - a real-time 3D space simulator, procedural universe generator and visualiser. It lets you explore the universe in three dimensions, starting from planet Earth to the most distant galaxies.
Space Engine vs Stellarium opinions
pros, cons and recent comments
Space Engine seems to be a game and not a star database for astronomy.
Negative comment • over 5 years ago
Space Engine contains many known planets and nebulas, you can get close to them, search them and even land on planets and view them from other angles
SkyView is powerful, easy-to-use app that answers questions about stars, constellations, and more. Simply point the camera to the sky, tap on what you see and discover neat things about these sky objects.