Ballistic AE and a Kestrel 4000 or 4500 in order to get DA. The reason I stress DA is because you're not going to have a weather station out in the middle of nowhere. If you use the Kestrel's (corrected) Barometric Pressure in your Ballistic Calc, you will need to correct the Kestrel before going out. Plus you may not have the same conditions where you're going (now you've added data from the location you came from). In order to correct it where you plan on shooting, you will need to know your current elevation (in order to get the corrected Baro Press and data). By using station pressure on the Kestrel, you'll get the correct DA no matter where you're at. Your DOPE will change a bit when you have at least a 5000' DA change.
Also, Ballistic AE has the Litz library, uses the JBM calculator, and you can true your DOPE if you need to.