Here is the full list of all 101 Little hidden city achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
the end of the game
find traffic light
find pointer
find statue
find solar_battery
find bicycle
find electric car
find flower_palicious
find satellite_talk
find power station
find basketball
find inflatable pool
find cat
find tractor
find medical bed
find wheelchair
find camera
find water_motocycle
find gazebo
find telescope
find sculpture_rock
find slide
find motorcycle
find air conditioning
find football_ball
find swing
find boat_old
find TV
find VOLGA
complete a level gas station
find extinguisher
find part of the train
find haystack
find engine
find army trailer
find barrel
find wheel_2
find strut
find wheel
find spare part
find logs
find muffler
find hovel
find soona
find old car
find canister_2
find canister
find equipment for garage
find Jack
pass_level_supermarket
find sink
find trolley
find moped
find handbag_female
find bananas
find drawer
find bucket_washing brush
find soft toy
find cake_shocolate
find eggplants
find jacket
find steak_sibs
find fish
find bank_register
find pac_products
find shoe
find carton
find stool
find basket
find watermelon
pass_level_country house
find plant_in_roof
find potty
find stairs
find watering can
find bucket of apples
find light
find log
find watering can_2
find Boots
find tools
pass_level_busstation
find newspaper
find nameplate
find suitcase_opened
find suitcase_02
find stroller
find shoes
find bottles
find bicycle_old
pass_level_apartment
find strap
find umbrella
find hat
find bag
find suitcase
find tube
find magnifying_glass
find coat
find book
start the game