Solar Info  is a app that it provides information on Sun´s diurnal motion and Sun´s position during the year, which facilitates the understanding of some phenomena which, despite being familiar to us, we sometimes do not fully understand.
It is a useful tool for installation and setting of sundials because it provides an accurate solar time, calculated using astronomical algorithms.
Besides, there are a widget that can be placed anywhere in the home and shows the solar time at all times, sunrise and sunset times and the Sun´s relative position in the sky (when the Sun is visible).
The solar time in widget is updated both automatically and manually when touching anywhere on the widget area. When pushing on the icon on the top right corner of the widget, you can access the app menu.
The start screen now shows the solar time continuously, which is updated every second, as well as the sun Azimuth and Altitude, Equation of Time and UTC. 
The Ephemeris section features the following information:
 	Latitude
 	Longitude 
 	Sun altitude
 	Sun azimuth 
 	Right Ascension
 	Declination 
        Distance
 	Morning Astronomical Twilight
 	Morning Nautical Twilight
 	Morning Civil Twilight
 	Sun rise
 	Transit
 	Sun set
 	Evening Civil Twilight
 	Evening Nautical Twilight
 	Evening Astronomical Twilight
 	Day lenght
 	Julian Day
 	Equation of Time
 	Local sideral Time
        GMST
 	Logitude correction
 	UTC
 	Solar Time
 	Cast shadow
 	Spring Equinox
 	Summer Solstice
 	Autumn Equinox
 	Winter Solstice

In the Location section, the location coordinates can either be obtained featuring several options :
•	Favourites list (offline).
•	Using the integrated GPS (it is required that the location is activated).
•	From the map (mobile data is required).
•	Manual (offline).
•	From an internal database containing 20.000 cities (offline).

It is now possible to change the location in the ephemeris module, which allows you to know the ephemeris of the Sun anywhere and at any time.

The ‘Equation of Time’ section shows a plot of the Equation of Time values. By moving the cursor, it is posible to see graphically the relationship between True Sun  and Mean Sun as well as the value of Equation of Time for a specific date.
Graph of Analema and its components, displaying its value for each day.
Graph of daily Sun Path and hourly analemma. Possibility to add a horizon mask and the illumination limits for a horizontal or vertical declining dial.
It is posible to change the year for which the Equation of Time is calculated.
It is posible to export the data from the Equation of Time to an Excel file for subsequent processing in a PC.
The location of the widget is automatically updated every hour.
If the device is set to adjust the Time Zone automatically, the obtained precision may be in the order of ±5 seconds.
If you want to help translate the application into other languages, contact the support email.

Bibliography:
- "Astronomical algorithms". Jean Meeus
-" La gnomonique". Denis Savoie
-"Formule e metodi per lo studio degli orologi solari piani". Gianni Ferrari

Information about the Sun and tools for building and understanding sundials.