Cats are considered lucky in Japan, and owners of the popular pets spend a lot on their care. But how can you tell when they're "feline" sad?
A tech firm called Carelogy has created an app trained on thousands of cat photos. They say it can tell you when your cat is in pain. Since its release in May, "Cat Pain Detector" has gained 43,000 users.
Carelogy teamed up with Nihon University to gather 6,000 cat photos. They carefully studied the positions of the animals' ears, noses, whiskers and eyelids. They then used a scoring system to measure tiny differences between healthy cats and those in pain because of hard-to-spot illnesses.
The app is already being used by some vets in Japan.
