The app allows pet owners to hold video consultations with vets, with 35 experienced, UK-based vet surgeons and nurses on hand to provide veterinary care advice.
As well as free video calls to nurses, it provides a free symptom checker, or the opportunity to talk to a vet surgeon for £20. There is no extra charge for using it out of hours, either.
Joii has experienced a “substantial increase” in users, with almost 30000 downloads in the past two months.
Paul Hallett, co-founder of Joii, said: “We understand it is a difficult time for everyone right now and we want to do whatever we can to support people through it.
“People and their pets have always been the key driving force behind our business, and we are now here for them 24/7. We can support pet owners from the comfort of their own home and we’re just a few clicks away.”