Your Complete Android Observatory
Available in English, Deutsch, Français, Italiano & Español
See Mobile Observatory in action
Twilight Sky
Day/Night on Earth
Solar Eclipses
Tonight in the Sky
3D Solar System
Orion Nebula
Live Solar Images
Know exactly when celestial objects become visible from your location
Calculate precise horizon profiles using NASA SRTM elevation data. See exactly where mountains, hills, and terrain block your view of the sky from your observing location.
The only astronomy app with real horizon data
An astronomy app first - know when objects clear your hills
Smart push notifications keep you informed
Point your camera and explore the sky
Real-time aurora and solar activity dashboard
Personalized recommendations for your location
Massive astronomical database at your fingertips
Plan your observing sessions in advance
Detailed Sun and Moon information
Start with Mobile Observatory Freemium, then unlock the complete observatory
Explore the Night Sky
Try Mobile Observatory Freemium
Your Complete Observatory
Get Full Observatory
Trusted by astronomy enthusiasts worldwide
"This app is simply fantastic and keeps getting better. It offers a huge variety of features, making it the most professional app in the Play Store."
"A fantastic update. I have always found this app excellent, and now it is even better."
"Version 4 is amazing: intelligently programmed, very well organized. Thank you for this excellent work!"
"Along with Stellarium and SkySafari, this is one of the best astronomy programs!"
Latest updates and improvements
Preview of upcoming features:
Draw Your Horizon
Saved Scenes
Observing Plans
My Observations
Log Observation
My Equipment
Edit Telescope
FOV Calculator
FOV Simulator
FOV Frame in Sky View
Optical Tools
Notifications
Observing Plan Generator
3D Topographic Landscape
Double Star Map
Variable Star Light Curve
Eclipsing Binary Predictions
Comet Light Curve
The story behind Mobile Observatory
Creator of Mobile Observatory
Wolfgang Zima spent years as a professional astronomer before finding his way into software development. After completing his PhD in Astronomy at the University of Vienna, he worked as a postdoctoral researcher at the Institute for Astronomy at KU Leuven in Belgium for five years. It was there that he discovered a passion for scientific software — writing tools for analyzing spectra of pulsating stars and building a CCD image simulator for ESA's PLATO mission, a space telescope searching for Earth-like exoplanets.
Mobile Observatory started almost by accident: when his Nokia phone broke on a mountain biking trip in late 2010, Wolfgang got his first Android phone and was surprised that no good astronomy apps existed. So he built one. First released in January 2011, Mobile Observatory has since grown into one of the most comprehensive astronomy apps for Android — with over 1 million downloads of the free version and 250,000+ of the Pro version — and has been continuously improved for well over a decade.
Wolfgang lives in Freiburg, Germany, where he works as a Senior Mobile Developer at sevdesk. He continues to develop Mobile Observatory with the same enthusiasm as on day one — now with the help of modern AI tools that let him bring new features to life faster than ever.
Start with the free Sky View or get the complete observatory experience.