iOS Game Center and Game Kit On App Store, the most popular app category among all is the Games category, something that even Apple accepts as a fact. And how this couldn’t be true, regarding that all or almost all iOS users have downloaded and played one or more games, at least one time? Personally, I’m quite confident that those users who haven’t (still) played a game, are limited from very few to none. There are various kinds of game players, from the fanatic ones, until those who play from time to time, as well as several kinds of games. However, there is one common element, no matter what kind of player each of us is, or what kind of games we like to play: Games are much more interesting when they allow players to achieve goals, or when they allow to compete or play against other players. In iOS and MacOS, this comes true through the Game Center network Apple provides, and through the GameKit Framework.
Let’s take things from the beginning, and let’s talk a bit about the Game Center. One could describe it as a social gaming network that offers multiplaying features, available for and used from iOS and MacOS users. Achievements, leaderboards, multiplayer gaming are some of those features. It was made available along with the iOS 4.1, and since then it’s been updated with new gaming options.
Game Kit Features
Game Kit provides three separate pieces of functionality:
• Game Center offers a centralized game service that connects players to each other. Game Center implements many different features:
o Friends allow players to create anonymous online personas. Users connect to Game Center and interact with other players through an alias. Players can set status messages as well as mark other players as friends.
o Multiplayer allows your game to create network matches that connect players through Game Center. Players can invite their friends or be connected to anonymous players. Most importantly, players can receive invitations to join a match even when your game is not running. Your game is running on each device and the instances of your game exchange match and voice data with each other.
o Turn-Based Gaming provides store-and-forward network match communications where the match is played out over a series of separate turns. This kind of match can be played without requiring all of the players to be connected to Game Center simultaneously.
o Leaderboards is adatabase that keeps score data. Its purpose is to allow users post their scores in a game and compare them with other players’ scores. It actually measures how well a player does in a game
o Achievementsare goals set in a game that players try to exceed during the gameplay. Achievements give players an inspiration to keep playing, earn as many of them as possible, and compare them with other players too. The important about achievements is that they are measured in points. A total of 1000 points are given to game creators in order to use them the way they want, with 100 points in maximum per achievement. Each game may use as many points as it’s needed, and the way it’s needed.
o Challenges allow a player to challenge other players to complete an achievement or to beat a leaderboard score.
Game Center is available on iOS and OS X.
• Peer-to-peer connectivity allows your game to create an ad hoc Bluetooth or wireless network between multiple iPhones in the same local area. Although designed with games in mind, this network is useful for any type of data exchange among users of your app. For example, an app could use peer-to-peer connectivity to share electronic business cards or other data. This functionality is only available on iOS. You can also get the same functionality using Game Center.
• In-game voice chat allows your game to provide voice communication between two iPhones. In-game voice relies on your game’s network connection to another user to create its own network connection to transmit voice data. This functionality is only available on iOS. You can also get the same functionality using Game Center.