Okay, yes I currently live in Illinois where deer hunting is shotgun/ML only but being older than dirt and hunting all over the country as well as having a large passion for the shooting sports and collecting firearms I do have many many many firearms. Other than my military collectables they all have a use/function and get fired on a regular basis. Now that that useless crap has been typed and out of the way, to the question at hand!

#1) If your firearm has a 12 inch POI shift at 75 yards between focal power shifts then you have a problem. Period, point, plain and simple. Now, the question is, is that problem you or the scope itself? 12" tells me it's more than likely the scope. If you were experiencing this problem at 200+ yards then I would maybe question whether or not you have a "fat" crosshair and you just weren't able to print a fine point on the target and you wandered around it. The older and cheaper scopes a lot of times were made with the crosshair on the second focal point and if you were using mildot then you had to do your drop and windage calculations based on one power because increase/decrease actually magnified/shrunk the mrads so ranging/windage calculations were different. Whole nother topic there, but they would also sometimes experience POI shift at various power levels with those older vari power scopes on the SFP type. Most mid range and above scopes nowadays are based off the first focal plane CH and rarely have this problem.

Your scope, with the Nikoplex ret. has absolutely NOTHING to do with that APP so you were talking to a jerk around BS artist on the phone. Contact customer service, tell them the problem again, and if they try jerking you around again by saying something about some stupid app tell them they are full of crap! Send the scope in for another one. Of course that is AFTER you check your rings and such for torque to make sure when you adjust power you aren't actually physically moving the scope a hair. (happens more than you think).