Here is the full list of all 52 Hidden Cats in New York achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
Finish with no Hints Advanced
Rooftop Bonus Level Completed
Found 750 cats
Smelly Cat Caffè Bonus Level Completed
Found 700 cats
Ninja Cats HQ Bonus Level Completed
Found 650 cats
Metro Bonus Level Completed
Found 600 cats
Found 550 cats
Museum Bonus Level Completed
Found 500 cats
Found 480 cats
Found 460 cats
Found 440 cats
Town's Park Bonus Level Completed
Found 420
Found 400 cats
Found 380 cats
Found 360 cats
Found 340 cats
Found All Cats Advanced
You found the Ninja Cat
You found the Super Power Cat
Found 320 cats
Found 300 cats
You found the Aracno Kitten
You found Principe
Found 280 cats
Found 260 cats
You found Cacau
Found 240 cats
You found the Alien Cat
You found Babalu
Found 220 cats
You found Oliver
You found The King Cat
Found 200 cats
Found 180 cats
You found Mingau
Found 160 cats
You found the Ghost Cat
Found 140 cats
You found Céu
Found All Cats Normal
Finish with no Hints Normal
Found 120 cats
Found 100 cats
Found 80 cats
Found 60 cats
Found 40 cats
Found 20 cats