I teach firearms safety, and so encounter many younger people regularly in the context of the shooting sports. I'd estimate one out of 1,000 actually engage in real shooting sports.
Apps on the Android or iPod? Games... Crude simulators... a few practical apps. Gun store guide? Not to my knowledge. First person shooters; zombies; action animations, etc...
You'll find useful stuff like "
Plink Log" and some
Shot Timers.
But, if you go into a mapping application like Google Maps on the Android platform, and then search on "Gun Store" you'll get lots of commercial hits. Here's what it looks like on my region using the PC Google mapping application:
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.