Watch Dogs 2's seamless multiplayer was broken at launch, but some of the features have been brought online today for PlayStation 4, with availability for Xbox One soon to follow. Should the update run smoothly "additional elements" to the multiplayer will be phased in, Ubisoft noted in a statement.
If you want to explore these features, you can invite other players for co-op, hack or be hacked by rival players and participate in Bounty Hunts, or have a bounty hunter invade your game. While we were able to play around with these features prior to launch, they did cause performance dips and crashes.
Per Ubisoft's statement, "The development team will monitor the online stability of the seamless multiplayer features and should everything continue to run smoothly, the additional elements and final phase of seamless multiplayer will be deployed: Nearby bounty targets and Prime_Eight rivals will join the player's world for them to hunt down and hack without going through the Multiplayer App in the smartphone. Players will also encounter friendly Dedsec hackers who can help them complete different Dedsec events throughout San Francisco."