Any use other than selling for items whose 'Recommended Use' is 'Sell"?
I've played the game and looked through the wiki, there is no use that I've seen for the miscellaneous items that you gather from loot chests and dead bodies. The names for everything is just filler, make the player feel a sense of pride when he picks up a Diamond or Smartphone. The only quest items you will gather would be herbs and leather, occasionally some other item that you can only get while performing the quest.