Blue cases in Astral Chain are basically the side quests of the game. Some of these are easy to find and others can easily be missed. check out this Astral Chain blue case guide to find and complete them all.
Astral Chain Blue Case Guide
We are updating this was we go so check back soon for more updates.
from GamersHeroes http://www.gamersheroes.com/game-guides/astral-chain-blue-case-guide/