Re: iphone calculator
I have BulletFlight, iSnipe, Ballistic and iStrelok. I haven't done much long-range shooting with my setup so I can only speak as to features and UI.
Of the four, iSnipe and Ballistic are the only two with automated weather updating. Often on a range day I'd just get weather data from iSnipe or Ballistic, write it down and transfer it to other programs; now I'm onto iPhone weather apps, of which there are several good ones.
BulletFlight has the best simplified interface, with iStrelok a distant second. iSnipe and Ballistic are both basically forms you fill out.
I would suggest either KAC Bulletflight or iStrelok. You may also want to look at Clinometer, ShotTimer and Gun Log for gun utilities, Spyglass for land navigation and spotting (slightly less toy-like than Theodolite which is similar), and wunderground.com's weather app (which can draw weather info from local radio weather stations).