Can I play the Final Fantasy XV mobile app without spoiling elements of the main game?

Based on information from Polygon article and FFXV: A New Empire, you can play the mobile game without spoiling anything from the main game.

There’s little in common between A New Empire and the game it’s based on

and

The game is set in the universe of Final Fantasy XV and features an alternate story which focuses on the development of Insomnia as a kingdom.

Further more, FF XV: A New Empire was not developed by Square Enix. It was developed

by Machine Zone, Inc. (MZ), under the name Epic Action LLC, licensing the Final Fantasy name from Square Enix

FF XV: A New Empire follows similar play styles of the companys other games, like Mobile Strike and Game of War: Fire Age, while licensed under the FF XV title and universe.