The Sims 3: Pets is an expansion to the game The Sims 3 on. Although the original Sims 3 game was on Nintendo DS, Wii, and 3DS, this game is only on 3DS. This game will use the same formula as The Sims 2: Pets. This game is namely different in the fact you may play as the pets.
- Human Sim
- Dog Sim
- Cat Sim
- There are 30+ Breeds of dogs
- There are 24+ breeds of Cats
- Play as Dogs, Cats, and Sims
- The 3 sim cap
- 3 saves
- The inability to age
- a Cursor system
- You can play as your own pet that you created.
- Pets have their own traits!
- Life stages for pets are: Puppy/Kitten, Adult, and Elder
- Pets can learn skills.
- Cats and dogs can learn to hunt, dogs can learn to locate collectibles and fetch your Sims a date.
- Players will be able to obtain new breeds such as a dog tiger husky, a dog panda chow, a cat skunk birman as well as other additional pets.
- There are also new pet motives, Destruction for Dogs and Scratch for Cats. 
- The karma powers from the original The Sims 3 returns in the 3DS version of Pets and some of the negative karma powers relates to animals. 
- There are more than 100 breeds of dogs and cats with traits that can be altered, such as fur length and pattern. 
- You can control the animals and they can have their own desires.
- You can assign features to pets and learn new skills, Your pets are also sims and can help your Sim.
- Pets can meet, fall in love and reproduce. Also, they can try to have puppies, kittens, and will also have family trees.
- Pets have inherited genetics.
- There is a new town for the Pets expansion, Sugar Maple Coast.
There are a total of thirty possible pet traits. In Create-A-Pet, each pet can be given up to two traits. Pets can learn up to eleven traits, and they can also "un-learn" them. A few traits cannot be learned. Some traits are unique to one species, and some can be for any species. There are also some traits that will conflict with one another, such as Likes Swimming and Hydrophobic.