NavList:

Jim wrote

Try the app on your phone and on the tablet at the same time.  On one device set a delay... say 10 seconds.  Zero on the other.   Use the same body and all other settings the same on both.  Press pause on both simultaneously.  I think you will find the stopped time will be the same but the altitudes will differ by the change over that interval. You have to reduce the displayed time by the delay seconds.  

Thanks. I did what you suggested and  now understand how the delay function works.

A very useful app that gives UT, altitude and azimuth for the sun and venus. And it is in a large font that can be read in bright sunlight .I think that at noon I will watch the sun hang. I will know exactly when to take a noon sight but cloud may be a problem.

DavidC