I surprised myself today, I think I bought the most expensive app (program) for my iPod touch. It cost me a whopping 10bucks. But it's called "isnipe" and it's a ballistics program that's always going to be on me now instead of a cheat sheet being taped to my rifle.
I found something kind of weird out just now with it though. I've been putting in stupid setting to do with shot angle, temp and just other nonsense. In the picture I've got the temp set to a crazy +256C just to see what would happen......the bullet actually picks up speed. The shot angle is still set to 0 also.
On a serious note though, this is a pretty cool and simple to use app. It had just about every factory load that I can think of as well as every caliber. If your not using factory load, you can put your own bullet weight, BC and muzzle energy in into the spots provided. You can even save it so your not wasting time putting it in over and over.
Once your done that you can even put your rifle set up in. You can't pick a brand/model though. But you can put your rifles name in and the. Set the distance your zero'd at and save it. Then you can move onto the "fun" part of the program.
After you've got your rifle and ammunition all set up you can start picking your distances. You can have as close or as far a distance as you'd like and can also set the intervals for the cheat sheet that'll be produced.
The last option I gives you is your environmental in puts. If you've got an iPhone or 3G capable device, you can just hit a button and it'll figure all of that out for you. Once everything is set you simply hit "compute" and it shows up in a nice little chart.
One of the great things about this program is that it also has a built in range finder. Now obviously it's not a laser range finder, but it does work for the small bit I've messed around with it. You have to have a device with a camera on it to have the range finder be of use.