Sky Map represents a significant open-source achievement in mobile astronomy applications, offering Android users a handheld planetarium experience. Originally developed as Google Sky Map before being donated to the community, the application leverages device sensors to provide real-time celestial identification through an augmented reality interface. The app displays stars, planets, constellations, and deep-space objects aligned with the device's orientation, creating an educational tool that makes astronomy accessible to beginners while remaining useful for enthusiasts. The core functionality relies on precise sensor calibration, with automatic mode using the device's compass and accelerometer to track movement across the night sky. Manual mode allows users to navigate the celestial sphere through touch controls when sensor accuracy becomes problematic. The application features search functionality for locating specific celestial objects, zoom capabilities for detailed examination, and information cards providing scientific data about identified bodies. Performance depends heavily on device hardware capabilities, particularly the presence and accuracy of magnetometers and GPS systems. User experience varies significantly based on device compatibility, with well-calibrated sensors delivering smooth, accurate tracking while older hardware may require frequent manual intervention. The interface maintains a clean, minimalist design with adjustable brightness settings for night vision preservation. Real-world usage patterns show most users employ the application for quick celestial identification during evening observations, with educational settings using it for astronomy demonstrations. The figure-eight calibration motion, as noted by user June Farmer (2025-03-07), proves more effective than the recommended three-direction method for many devices. User feedback trends indicate widespread appreciation for the application's educational value and open-source nature, though hardware dependency creates inconsistent experiences across devices. Kyle Beach (2025-04-03) notes the application 'shows more than I am looking for almost every time I open it,' while Tolar Powell (2025-03-02) reports 'really bizarre results' on older Samsung hardware despite correct GPS and time settings. Positive reviews frequently highlight the application's accuracy when properly calibrated, with Dazy Katz (2025-02-28) noting astronomy professionals' surprise at its precision when using high calibration settings. The application's primary strength lies in its successful democratization of astronomical tools, though limitations emerge through hardware dependency and occasional calibration challenges. Ideal use cases include casual stargazing, educational environments, and supplementary telescope alignment. While not replacing professional astronomical software, Sky Map provides remarkable value as a free, open-source tool that makes celestial navigation accessible to Android users worldwide, particularly those with devices featuring reliable sensor arrays.