The app offers both a 'Simple' calculation with years/meters, wind speed and wind direction as well as a 'Complex" calculation that includes altitude, rifle angle, temp. The neat thing is if you could get a mount like the KAC guys offer for the M110, then the rife angle/degrees functionality of the iPod/iPhone would come in handy.
It would be nice if it had more 'built in' ballistics specs, but getting the info from the net is not that hard.
You can't go wrong for $12
/cl