This app is the only app available to date to calculate accurate zemanim for the airplane on your Android phone and it is easy to use (watch the video above). It uses the powerful GPS of modern phones to follow the position of the airplane and allow users to even daven k'visikin to 1-2 minutes accuracy (assuming flat terrain). Basically, with this app, there is no longer any excuse for not knowing accurate zemanim for the airplane. You can also use it to calculate z'maney ha'yom for anywhere in the world.
Among the features in this release:
1. Can upload flightaware Google Earth kml files to predetermine routes
2. Edit the route by clicking on the map or just use the default Great Circle Route
3. Both online and offline maps and html documentation built in.
4. Calendar tool for choosing departure and arrival dates and times
5 Extensive list of departure and arrival airports. Can also define ones not on the list.
6. Uses a simple flight plan to increase accuracy of zemanim that occur near take-off and
landing. During an active flight, the flight plan can be improved by using the "Fix Posit"
button to make the predicted position coincide with the actual position.
7. Calculates several types of zemanim:
a. Z'manay Ha'yom at the clicked point (including solar altitude and azimuth)
b. Time to upcoming zemanim at the clicked point (so you won't daven incorrectly).
c. Airplane zemanim predictions corresponding to Chai Air Times tables.
Color coded markers are positioned on the map to show when the zemanim are
predicted to occur. The corresponding zemanim are also similarly color coded in the
zemanim chart for user friendliness.
8. If GPS geolocation is not available use the "Predict posit" button to show the predicted
position of the airplane based on the flight plan and entered dates and times. Use the
"Fix Posit" button to tweak the flight plan when the flight is active by making the
predicted location coincide with the real airplane button.
9. If GPS geolocation is available (you need to be near a window -- so book a window
seat) then push a button to show the airplane's position in real time using your phone's
GPS. Use this utility to even daven k'visikin to 1-2 min accuracy (i.e., sunrise is
when the GPS position coincides with the day terminator).
10. Displays the day-night terminator taking mean atmospheric refraction into account.
This feature is essential for determining the accurate position of sunrise and sunset on
the map. N.b., this feature is not available in almost any other website and certainly not
in any app, even though it is essential for following sunrise and sunset on the map.
In short, a tremendous tool for the airplane traveler....