Horse Armor
Minor DLC with no randomization involved. New items, equipment, abilities, etc.
It's Not Gambling, We Swear
Loot boxes with randomized contents, buyable with real money
Infinite Money Hole
No upper limit on in-game purchases
Changing The Game
Content with gameplay-altering effects, buyable with real money
Time Is Money
Game allows you to pay for speedy/instant access to things that can also be gotten through gameplay
Table For One
Multiplayer contains additional monetization, but single player doesn't
Detailed Info
Uncharted 4's single-player campaign is a complete package from the get-go. There is nothing to purchase apart from the game itself.
The multiplayer mode features two currencies - "Relics", acquired by playing the game, and "Uncharted Points", purchased with real money. Uncharted Points come in packs of varying sizes, from 300 points for $3 to 10,000 points for $50. Uncharted Points can be spent directly on various unlockable items, both cosmetic and otherwise - Relics cannot.
Both Relics and Uncharted Points can be spent on various different kinds of chests, which feature one or more random items. Chests are divided up into "Vanity" chests (which are purely cosmetic), "Gameplay" chests (which contain weapons and other gameplay-affecting items), and "Boosters" (which contain single-use gameplay-affecting items). Vanity and Gameplay chests will never contain items the player has already unlocked. All items available through direct purchase with Uncharted Points can also be found in chests - nothing is exclusive to those who pay extra.