Are there any server-side APIs/libraries/services which are considered some sort of standard for creating multiplayer games for iOS, maybe even some part of the iOS/XCode technology stack? Or would every real-time multiplayer game typically have a bespoke server just like PC games would?
What about handling players in different locations around the world, etc - is it up to the developers to have multiple servers or do Apple provide any server facilities as part of deploying your game on the app-store?
My impression is that an iOS game is nothing special, it's just a program which talks to a server via typical network communication, so I could have Android players playing against iOS players... but you rarely seem to see this scenario which made me wonder if there are some lock-ins on the technology.
If anyone has worked on a multiplayer iOS game I'd love to hear how you approached this.