I'd like the orrery to be significantly different than programs like Stellarium, because: 1) Stellarium is far more beautiful than anything I'm going to write in may spare time and 2) Why duplicate Stellarium? With the orrery, I'm trying to provide much of the information available from sources like the Astronomical Almanac (http://asa.usno.navy.mil/). I want to make it easy to see what the sky would look like anywhere on the earth at any time in the past or future (Well +- 3000 years or so), and to make it easy to plan ahead for unusual events, like the triple total solar eclipse on Jupiter that is coming up on October 12th this year.

So my emphasis is to try to make a tool that will answer questions like "When is the Perseid meteor shower, and will the moon wreck it this year?" or "Will I have moonlight when I go camping next August?" or "What's that bright thing that's been in the western sky after sunset the last few evenings, and how much longer will it be there?". All this stuff is available on the web, of course, but I'm hoping that my app will make things like that easier to find, or at least easier to find in a format customized to your current location. I also want to avoid having the app grab information from the internet, because people are most apt to look at the sky carefully when they are away from city lights, perhaps camping or hiking, and I want the app to have full functionality in the remotest of locations, where there may be no signal for your phone.

So after adding Solar Eclipses, I'm thinking about integrating the tool with the phone's calendar, so that it can mark your calendar when, for example, a lunar eclipse will be visible from your location, or when Mars is at its brightest, etc.