Thank you for the explanation on the G1 and G7 factors. I shoot a 7mm rem mag and I just started using the Strelok app on my samsung. It seems to be inline with stats from my nightforce program on my desktop. I did miss my Monster buck at 600 yards but I blame it on my scope mounting more than anything else. Some how the bolts came loose on my picatinny rail. I spotted the deer and ranged it, when i grabed my gun i noticed the scope was loose. I opted to go for the shot anyway. I shot right over the back at 570 yards. I have since re mounted the scope and used the blue locktight on the threads. I have not tried to duplicate the shot yet. I need to practice allot more 600 to 800 yard shots with my set up now that I have dialed in my hand loads. I shoot a Berger 168 Grain at 2912 MV. I hunt at about 10,000 feet. So far I like all my options on the Strelok app. I like having the pre printed laminated cheat sheet taped to my stock for quick refrence rather. You won't always have time to mess around with the phone or you may loose your shot opportunity.