I have emailed the app to all of you that have responded. Thanks.

The version I sent out is very limited, but it should be enough to get the concept of what I'm trying to do, and hopefully it will install and run on your devices.

I forgot to mention in the email that there is an Options menu. There will be page sensitive help, but only the main page has that help right now. Basically every calculator saves its state so that when you come back to it, it has what you last calculated. There is a global setting for the rounding precision that can be set from anywhere.

I plan to have explanations of what Pitch Speed is and why you would want to calculate it. I will have explanations for all of the calculators and graphics where possible.

The Engine Size calculator will go up to 12 cylinders. Not many model engines have 12 cylinders. Some have 4, and I've seen 5. But I went ahead and made it so that it could be used by (real) car guys.

The basic theme of the calculators is being able to calculate from different directions and in different measurement units. It makes the programming a bit of a challenge, But it makes thinking about what you are trying to figure out easier, at least to me.