I really enjoy this game in every possible way. I like testing things, so I did this with Fallout Shelter too, and i recently found a glitch, or an advanced way to get those Shiny Legendary items.
All you need is to get some lunchboxes, and then, do a copy of your "VaultX.Sav"
Open the lunchboxes, and if you dont get any preferred items, you just copy paste your copied save file into your mobile device and then open those lunchboxes again. The game randomly generates new items. You can do it over and over again, till you found some Legendary stuff.
I don't know whether im the only one who found it, but i feel like, that this method destroy the exciting feeling of opening lunchboxes. Not to mention the advantage you get.
Does anybody encountered this before?
Sorry for my bad English, its not my native language.