Key points of Watch_Dogs - Shops, bars and restaurants
Pawn Shop - here you can acquire chemical and electronic components to you gadgets and also sell found jewelry
Pharmacy - place, where you can buy medicaments, which are crafting components
Guns store - sells weapons and ammunation
Clothing store - here you can buy new outfits
Tobias's Shop - sells homemade gadgets
Restaurant - in restaurant you can hide from police chase or rob it for money
Cafe - in this place you will find chess players
Bar - in bars often hang around oponents to drinking games
In the virtual Chicago, there are four types of shops available where you can buy components for crafting various gadgets, firearms or rob, which provides a small monetary gain for your character.
Pawn shop
One of the local pawn shops
Pawn Shops are ones of the more interesting places, because you can buy three types of elements for crafting, there: Electronic parts, chemical components and volatile chemical components.
You can earn quite a buck, after you sell what you have found
Apart from purchasing, it is the only place where you can sell the items that you found in the glove compartments of the cars that you stole, watches, necklaces and the other valuables.
Drugstore
A regular drugstore
You will not be frequenting drugstores too often. The only thing that you can buy there are vials with medicine.
Clothes shop
Clothes shop
The city does not pamper you with too many designer clothes. The available clothes shops are identical and you can find the same stock in each Changing your clothes does not influence the single player gameplay in any way, but can help you stand out in the crowd, in multiplayer. Some of the clothes are available after you unlock them (e.g. Digital Trips).
Gun shops
The players' favorite shops
In the city, there are several shops with various weapons. It is a good idea to visit them often, to have access to full supply of ammo and to buy the mightier and mightier tools of enemy immobilization. While viewing the weapons, you can also access their descriptions, thanks to which you can always find something for yourself.
Tobias's shop
In spite of what it may seem, Tobias has good and relatively cheap assortment of goods
After you complete the mission, in which you gain access to the bunker, Tobias offers you is services, which consist in preparing homemade gadgets. For a pay a bit higher than the components themselves, the man will sell you any tool, like grenades, jammers, even if you do not have the skills to craft them yourself. His shop is located under the highway, close to one of the entrances to the bunker. That is why you can visit him pretty often, without walking extra way.
Heists and discounts
The discount for the grenade launcher and the automatic shotgun at the Guns Shop
In the gunshops, there often are discounts. If you are not in a hurry to buy a weapon, frequent the shop - often, you can find a discount. The items that are on sale, at a discount price, are marked with the "Sale" marking and are marked in light green, at the beginning of the list.
The shop heist
Each shop in the game can be robbed. It is enough to target your weapon at the shop keeper, after which you get the option to collect the money. These are not too big sums - most often they are around 1000$. As for the police, they may (but do not have to) be alarmed after the phone call from one of the customers but, at any moment, you can incapacitate them or use the jamming gadget.
Bars and restaurants
A small restaurant in Chicago
Chicago could not be short of multiple bars and restaurants. This is where you find the unique drinking challenges and chess challenges. Also, here are the loudspeakers that play song. It is a good place to pick up a song, with the SongSneak. Of course, each bar/restaurant can be robbed, just like any typical store. The only thing that you can buy here is a beverage. It regenerates Focus and extends the maximum health bar, temporarily.
Gambling machine
In some of the places, there also are slot machines. Very often, only one pull causes you to win several hundred, or even several thousands of dollars but, most frequently, attempts to break the bank end up in failures. This is why you should not use them for an extended period of time, because you will ultimately start to lose money.