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.
Found 20 cats
Found All Cats Normal
Found All Cats Advanced
Finish with no Hints Normal
Finish with no Hints Advanced
You found the Ghost Cat
You found Cacau
You found The King Cat
You found Principe
You found the Aracno Kitten
You found Mingau
You found the Ninja Cat
You found Babalu
You found the Alien Cat
You found Céu
You found the Super Power Cat
You found Oliver
Found 40 cats
Found 60 cats
Found 80 cats
Found 100 cats
Found 120 cats
Found 140 cats
Found 160 cats
Found 180 cats
Found 200 cats
Found 220 cats
Found 240 cats
Found 260 cats
Found 280 cats
Found 300 cats
Found 320 cats
Found 340 cats
Found 360 cats
Found 380 cats
Found 400 cats
Found 420
Found 440 cats
Found 460 cats
Found 480 cats
Found 500 cats
Found 550 cats
Found 600 cats
Found 650 cats
Found 700 cats
Found 750 cats
Town's Park Bonus Level Completed
Museum Bonus Level Completed
Metro Bonus Level Completed
Ninja Cats HQ Bonus Level Completed
Smelly Cat Caffè Bonus Level Completed
Rooftop Bonus Level Completed