It's well worth taking time out from the main singe-player campaign to hunt down these easy-to-find phones left lying around by Maurice. Not only will you unlock an extra trophy or achievement for doing so, the story that's played out as you grab them will add much more meaning to the final decision you face once the credits have rolled.
Each phone will be marked on your mini-map if you've cleared the local ctOS Tower, so we recommend doing just that before you try and hunt down each device. It also doesn't matter which order you collect these phones in, as the audio story is played out in a specific order.
Watch Dogs burner phone locations
Burner phone 1 - Bottom of the Eighth
This one's a piece of cake to find. You'll actually come across this one as you play through the game's very first mission, Bottom of the Eighth - you really can't miss it.
Burner phone 2 - Pawnee
You'll find the next burner phone in the northern Pawnee district. You can find it on the roof of the motel, tucked away just behind the last letter of the sign. To get up on the roof, simply climb up the yellow ladder on the left of the building as you face it, then head across the roof and grab the phone.
Burner phone 3 - Pawnee
While you're in the Pawnee district, make sure you grab the other nearby phone. This one's located at the rear of the trailer park, just over to the left. Drive in and look for a smashed up old blue car. Get up on the roof and you'll be able to pinch the phone.
Burner phone 4 - Pawnee
There's one more phone to be grabbed before you leave the Pawnee area. Look for the restaurant that claims to have the fattest hot fish sandwich. When you've found it, go through the left-hand gate as you look at the building from the street. Now look for the shed at the rear of the yard and grab the phone from the tool chest inside.
Burner phone 5 - Loop District
Next, head over to the Loop district. The phone itself is located beneath a freeway where Chicago's homeless are sleeping. Check the beds behind the fence to get your hands on the phone.
Burner phone 6 - The Wards
This is the only phone located in the Wards district of Watch Dogs, and it's found somewhere inside the ghetto. Make your way to a courtyard located near some very run-down buildings. Look for a burned out structure, then take the phone from the third floor.
Burner phone 7 - Brandon Docks
Make your way towards the Brandon Docks district, then look for a big industrial building. Perform a hack to open up the gate, then go through it and head up the stairs to your left. Turn right when you reach the top, then take the phone from the mattress near a burning barrel.
Burner phone 8 - Brandon Docks
The final phone is also located in Brandon Docks. Head to the other industrial building, but this time head up the stairs on your right. You can't miss the phone now - it's sitting right on top of the desk in front of you.
Now that you've collected all eight burner phones, you'll unlock the Sanity Check achievement or trophy, depending on the system you're playing the game on.
You can find the rest of our Watch Dogs game guide from the index page of this walkthrough.