Well inFORMED Trophy
Collect all Dead drops.
Dead Drops become collectible once again only this time, they are carried by carrier pigeons flying around the city. Aside from earning your first Dead Drop as part of a story mission, you'll have to find the others yourself. They'll be automatically listed on your mini-map in the form of a blue pigeon icon when you get close. Collecting them will reveal the back story of the characters across the game, shown in the form of audio logs. For 19 you will need the Improved Static Thrusters, see "Back to Bayou" for a guide on how to reach that area.
There are a total 30 Dead Drops scattered across the game. Note that the map is meant to be used in compliment to the video.
Locations are as follows: