Useful Ballistics Apps for Computing Trajectories.
Apps are for generally for PC's, MAC's, iOS, and Android devices. Search the web and/or your appropriate App Store.
AB Quantum Ballistics
Hornady 4DOF
iStrelok
Ballistics Advanced Edition
KAC Flight
iSnipe
Nosler Ballistics
Shooter
Winchester Ballistics Calculator
Reference Books for the Advanced Shooter.
These are essential references for understanding the fundamentals of exterior ballistics, trajectories, and the factors that influence bullet behavior in flight.
Applied Ballistics of Long Range Shooting by Bryan Litz. THE authority on bullet behavior.
Accuracy and Precision for Long Range Shooting by Bryan Litz. The essential volume for long-range and extreme long range precision shooting.
Long Range Shooting Handbook by Ryan Cleckner. Basics of ballistics and shooting fundamentals.
The Wind Book for Rifle Shooters by Linda K. Miller & Keith A. Cunningham. Essential information for reading wind and its effect on bullet flight.
Modern Exterior Ballistics: The Launch And Flight Dynamics Of Symmetric Projectiles 2nd Ed. By R. Mc Coy. Excellent basic training manual available online at the link following.
Read on archive.org →The Precision Rifle Handbook by Frank Galli with Chris Way. A very different approach to calculating trajectory. Commonly referred to as Gravity Ballistics.