I have been using the " Ballistic Field Tactical Edition" app for well over a year with great success. It inputs all the parameters you asked about, and more if required. You pay an up front price only and get free updates when new bullets, loads, and features are released.
That's just the price from iTunes right? It's 19.99$ on there!
"The only thing necessary for the triumph of evil is for good men to do nothing"