The Android app which has gone free next as myAppFree app of the day is Astrolapp Planets and Sky Map. This app shows the path of your solar system and objects in the sky, including the orbits of the sun, the moon and the planets , in the style of a medieval astrolabe.
Astrolapp Planets and Sky Map Features:
* Planisphere showing the positions and motions of the Sun, the Moon and the planets
* Display of the 9096 brightest stars and the 48 Ptolemaic constellations
* Moon phase and phases of the planets; Retrogradicity of planets
* Precise numerical position data for stars and the Solar System’s objects in an ecliptical, equatorial or horizontal coordinate system; either heliocentric, geocentric or topocentric
* Real time mode or manual mode, the latter allowing to “scroll the sky” into arbitrary centuries
* Automatic detection or manual selection (optionally via a map) of the observer’s geographic location. Save locations to permanent memory.
* Graphical display of the ecliptic and the positions of the zodiac signs
* Optional height and azimut lines
* Calculation of local solar time and local and Greenwich sidereal time
* Zoom into the graphical display, i.e. to observe transit events in real time, or in history or future
* Night mode (monochrome black/red)
* Projection with center in the north or south pole of the celestial sphere, depending on the position of the observer