Re: hand held ballistics calculators
If you shoot inside of 1000 yards, you can get a lot of mileage out of iPhone/Android apps like BulletFlight, Ballistic and Shooter. Having a weather gage like a Kestral is important, but if even if you don't some apps will push atmospheric data (assuming you're in a location with a signal) directly to the app. This is obviously not as accurate but at least it's an option.
Of course, a good DOPE sheet is all most people need inside of 1000 yards, but having a ballistic calculator can really speed up the process of getting that DOPE in the first place.
Beyond 1000 yards things start to get tricky. Accurate localized atmospheric values become very important, as are your wind calls, obviously. Also, the variables used by the calculator need to be more precise. This is where the more simplistic apps start to fall apart and the high-end calculators like Patagonia Ballistics or Field Firing Solutions come into their own. They tend to include more advanced features like integration with mil-grade LRFs, BC confirmation and recomputing, etc.
So my point is there is a lot of inexpensive options to choose from if you're shooting medium to long range. In fact, I spent four years running different apps on an iPod Touch that I ruggedized with an Otterbox case (about $300 total). However, this solution has been suboptimal for ELR shooting and that's where FFS and the Nomad come in.