Unlike, say, GTA, Watch Dogs 2 doesn’t have a completion tracker or percentage bar to let you know how close you are to 100%ing it. The closest thing you have is the achievement list, which can, if nothing else, point you in the right direction. Here’s the full list of them and how to get them.
Story Achievements - Unlocked by playing through the main and side Operations
Who am I? - Complete the Wipe Your Profile main operation.
Put Your Damn Pants On - Buy a new set of pants after losing them in the prologue party.
Knight Ridden - Finish the CyberDriver main operation.
Baby I Got Your Money - Finish the False Profits main operation.
No Place Like Haum - Finish the Haum Sweet Home main operation.
Picking Up the Pieces - Finish the Looking Glass main operation.
Informer - Finish the Limp Nudle main operation.
Sabotage - Finish the Hacker War main operation.
Hypnotise - Finish the W4tched main operation.
Old School Justice - Finish the Eye For an Eye main operation.
Joined the Mile High Club - Finish the Hack Teh World main operation.
Make Every Voice Count - Finish the Power to the Sheeple main operation.
The Itsy Bitsy Spider - Finish the Robot Wars main operation.
You’re on a Boat! - Finish the Shanghaied main operation.
Hack The World - Finish the Motherload main operation.
Pimp My EKart - This will unlock during the Ekart side mission.
Leaks and Leaks - Finish the Ubistolen side operation.
The Fox - Finish the Shadows side operation.
100% Legit - Finish the $911 side operation.
Game Achievements - Unlocked by completing various tasks in and around the game world
Roboteer - Hack any robot. Unlock the Robotic Exploits skill to complete this one.
App’ing Around - Buy all the apps on the app store. You can do this at any point but you might as well do it when you need to get the Nudle Maps app right at the start of the game.
In Style - Buy the (hideous) Gatorfeet Whine Country shoes from any Plainstock store.
DedSec-A-Roni - Ride a tram. Wait until one slows down and the open area at the front should give you a “ride” option. Get off again to get the achievement.
Doggyland - Pet dogs 10 times. Doesn’t matter if it’s the same dog or different ones.
Only God Can Judge Me - Buy a T-shirt from the vending machine on the Nudle Campus.
PhotoBombed - Get photobombed whilst taking a selfie. Opening your camera app on any crowded street will have anyone nearby trying to do this so it’s not hard to get.
A Ride to Remember - Find and drive one of the unique vehicles.
Something to Ride - Highjack a bus.
Bad Boys - Highjack a boat.
Third Time’s a Charm - Perform 3 jumps in a row in a vehicle. This is almost guaranteed to be unlocked during the CyberDriver main operation.
Miniroadtrip! - Drive 4km in the Merengue vehicle. You can buy it from the Total Motors store in Prescott.
Knock You Out - Take out 30 enemies with melee who were unaware of your presence. This should unlock during the course of your playing the main story, but if not, there are plenty of restricted zones around the city that can provide ample opportunity to pick this one up.
Hold My Hair - Catch someone puking in the background of a selfie. The easiest way to do this is to stand outside of a bar with the camera at the ready and wait for the magic moment.
Feeding Frenzy - Put an APB Suspect Located out on the donut guy at Doobie Donuts, north-west of Painted Ladies.
Earn Your Sea Legs - Do a boat race. Note you don’t need to win, just finish one.
I Get Around - Do a drone race. Same rules as the boat race, don’t need to win to unlock.
Ain’t No Stopping - Do a motocross race.
Smooth Felon - Get a level 5 wanted level, then lose it without dying. Best done during the late game as you’ll have access to skills and weapons that can make this a lot easier.
Jump Around - Do a 140m jump. Easiest way is to do the Marin Madness motocross race and hit the jump at the end, but if you get yourself a sufficiently fast vehicle and find one of the jumps around the map, you should be able to get it. The Driver SF mission with DareDev!l Liv are also a good chance to grad this one.
Shutterbug - Take pictures at 25 Scout X locations.
Menace - Buy any 2 handed weapon from the 3-D printer.
Let Me Ride - Ride a car for 200m that you’ve hacked. Best done on a clear, straight bit of road.
One-Man Garage - Buy 25 cars in dealerships. Best way is to bounce between the various dealerships, only buying the cheapest cars in each of their selections.
Researcher - Find and collect all the Key Data around the map.
Graduation Day - Complete all other Trophies (not available as an achievement).
Multiplayer Achievements - These can be unlocked by playing the online multiplayer.
One of the Gang - Complete 5 DedSec Events. These are listed in your DedSec app as well as being out and about in the game world, so you won’t have much trouble finding them. You can also complete these solo if you want.
Natural Born Killer - Neutralise (stun or kill) one Hunter in the Bounty Hunter game mode.
Please Marcus, Don’t Hurt Them - Neutralise 5 Fugitives in the Bounty Hunter game mode.
Hold My Hand - Complete a co-op operation with another player.
Troll’r - Successfully invade and hack another player.