Facebook game developer OMGPOP, known best for Cupcake World, debuts on iOS this summer with Puppy World. According to the developer, the game has been downloaded over one million times since its July 20th launch.

Puppy World is an animal husbandry app in which players raise and care for canine critters. The premise is that Puppy World is being threatened by an evil cat named Lil’ Grum and in order to fend him off, players must unite the puppies they raise with children in order to generate “Puppy Power.” Caring for puppies involves purchasing a bed upon which they can place a puppy. The puppy costs a small sum of the in-game currency “Bones.” As the game progresses, the puppy grows into a mature state and can be cared for via washing, feeding, or brushing.

The game is controlled through tapping icons to activate puppy care actions, and finger-dragging to pick up and use various items — e.g. rubbing a sponge over a puppy during washing time. Once finished, the puppy becomes happy, and can be united with a child, earning the user experience and Bones. The more expensive puppies available for purchase take longer to mature, but yield more rewards when united with a child.

Beyond this repetitive process, the only other mechanics for players to delve into is decorating their virtual nursery and completing arbitrary quests. In terms of the former, new decor, puppies, and beds unlock at higher levels.

A distinguishing feature of Puppy World is its cross-promotion activity with OMGPOP’s Facebook applications. CEO Dan Porter tells TechCrunch that 20 percent of the game’s 1 million downloads are from cross promotions driven both by Facebook and by the developer’s website, while another 20 percent comes from paid ads. Players are also able to share in-game accomplishments via Facebook, further promoting viral growth. It is not immediately clear if the existing Puppy World cross-promotions on Facebook are now in violation of Facebook’s updated Platform Policies that forbid social games from linking off to competing social platforms.

As far as monetization goes, the game leverages in-app purchases for two types of currency — Bones and the more valuable Gems. Both can be bought in different quantities ranging in price from $0.99 to $99.99 with the former used to purchase premium virtual goods or to expedite the maturation of new puppies. Porter says that the game is making around $20,000 a day.