I had iSnipe and didn't get along with it. Most probably not the software's fault, I expect, but never the less. . .
If you have an iPod/iPhone 3GS or better (I think) Shooter will work with it. I just purchased Shooter (iTunes - 9.99).
My iPod is a bit out of date but an email to Sean, the developer, said he'd see what he could do. I like that kind of response.
My iPod is hacked, whatever that means so I can use a bluetooth GPS, which is at least, if not more so, than ballistics software. A fella has gotta know where he is when he's lost.