I am looking for a way to establish a wireless connection between an iPhone and a desktop client. Gamekit looks promising but all the examples / documentation only explain iPhone to iPhone.
Are there examples / documentation for an Gamekit peer on the desktop (cocoa or java)?
What are the alternatives without doing to much low level socket programming?
The iPhone emulator does not run these bluetooth p2p connections. Hence, it can only be tested with real hardware.
It is a little confusing because the GKSession reference talks only about being a way to connect peers over bluetooth, while the GKPeerPickerController states "can be configured to select between Bluetooth and Internet connections." However there's a clear note there that they're not really going to help you with internet based connections.
This is unfortunately a non-answer, but...
GameKit is an abstraction of the bluetooth and wifi networking layers, allowing a specific set of protocols for communication between two devices -- to communicate with a desktop client, you would need to replicate all of the GameKit functionality on the desktop, since there is no comparable API on the desktop. This would not be a simple undertaking.
I would highly suggest developing something over bonjour, as #Jordan suggested. Bill Dudney's project (blog article). It's a great place to start.
Citing Game Kit Framework Reference's Features paragraph:
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.
Related
This might seem like a dumb question, but can GameKit be used for apps other than games? That is, will Apple approve an app that uses GameKit for bluetooth purposes but doesn't use them for games? Or will they reject it based on "misuse of hardware/software" or whatever that rule is?
From Apple's "Game Kit Programming Guide":
Peer-to-peer connectivity allows your game to create an ad-hoc Bluetooth or local wireless network between multiple iOS-based devices. Although designed with games in mind, this network is useful for any type of data exchange among users of your application. For example, an application could use peer-to-peer connectivity to share electronic business cards or other data.
This clearly answers your question.
Yes, GameKit can be used for things other than games, in fact, in some situations it is better than using other communication frameworks, as it is ridiculously simply to create a local network connection between two devices, and you can send any data you wish over the connection you create.
the gamekit over wifi documentation talks about local wifi and that it's built on top of bonjour.
Does that mean it does not work over the Internet, locating user/players in a different subnet, different ISP ... etc
If I need to connect to players/users on the Internet in general I assume I need to setup a server, right ?
YES, Game Kit can be used to connect peers over Internet.
BUT in this case your application must respond to peerPickerController:didSelectConnectionType: and handle all your private handshake protocol to discover peers and establish communication. A web service on your server is also required (unless users type in their IP address).
Good luck Sam!
References:
Apple IOS Reference Library, Game Kit Programming Guide.
Sanford University Online Course, iPhone Development, Lecture 17: Bonjour, NSStream, GameKit (see at 48 min 28 sec).
there are two things:
you can use gamekit to play with local devices using GKsessions
you can use gamekit to play over the internet using GKmatch
both methods are very similar, but it's not the case of just changing a flag - you will have to write code for each. if you are smart, you can make a small interface which can use both, based on a flag. I've implemented it and it works fine
I'm trying to write a simple chat application for the iPhone (as an experiment). Is there a simple way for two devices to discover each others' IP addresses, and given the addresses is there a simple API or protocol that would let me send text messages back and forth?
I've investigated SIP (specifically Sofia and eXosip), but these tools exist as C libraries and are beyond my current ability to port them to the iPhone.
Update: I'm trying to connect two devices over the Internet (i.e. not over Bluetooth or a local wireless network, which is what GameKit does).
You're going to need a server that provides the match making service. Game Center makes this pretty easy, but your users will have to have Game Center accounts.
Alternatively, you can set up an XMPP (formerly Jabber, it's what powers Google Chat) server (I've never done this, but there are several available) and use the XMPP Framework for Cocoa. There are instructions for using it in iPhone apps here.
I'm sure there are other chat servers and client source also available. IRC and Mobile Colloquy come to mind.
Finally, you could write your own server using your favorite server language / framework. This isn't too hard (I've done it myself), but it's far from what I'd call simple, and I wouldn't use it for a production system.
There is support for exactly this kind of ad-hoc peer-to-peer networking in GameKit. Have a look at the second half of the GameKit documentation for details:
http://developer.apple.com/library/ios/#documentation/...
NSNetService is a good option.
Take a look at WebRTC Datachannels. WebRTC is a newer option with native iOS support a standard that is still being finalized, but it is more flexible should the iOS app need to communicate with browser or even android peers
(I am not interested in pure theory, but as a practical near or mid-term possibility, say within 12-24 months.)
As a developer familiar with (but not specializing in) two major smartphone platforms, should I expect an Android library to come out which can spoof itself onto an iPhone app's GameKit-based network. It seems reasonable that a Bluetooth interface between platforms might square the opportunity to make useful applications, in the same way that modems benefited PC/Mac platforms via Metcalfe's Law.
I am looking for one of two answers:
Is this obviously not likely (e.g. because of encryption)? If so, what is the reason? Is it possible in principle, but requiring years of reverse-engineering (like SMB/CIFS/Samba)? Or is it a no-brainer and just a matter of time? Please give evidence supporting your reason.
Is there an alternative way to have direct peer-to-peer networking besides GameKit? For example, a hand-rolled network using Bluetooth or ad-hoc WiFi? It would be nice to spoof an Android device into an existing iPhone app but my main question is, can the devices speak with each other at all!
Yes, it is possible. GameKit is a protocol using TCP and/or UDP over a BNEP Bluetooth connection. It also uses a trick to identify other iOS devices using the Extended Inquiry mechanism in Bluetooth 2.1+.
I was able to simulate the EIR responses, now, someone needs to reverse engineer the GameKit protocol. This doesn't need Bluetooth, as it is also used for GameKit connections over WLAN.
If anybody can re-implment GameKit for WLAN connections, I can finish the Bluetooth version.
No, and it wont come soon or even at all... Apple pride themselves with their security features, and bluetooth connections can access private data. There will probably not be any cross platform bluetooth framework until something is agreed upon by both companies.
Bump as said by a previous answerer uses a remote server, and the data transferred is not via BT.
GameKit is Bonjour so a Bonjour (which is on IP) over Bluetooth on Android should work.
That should be possible as Bluetooth is capable of setting up tcp/ip networks. Though I have no knowledge of the IPhone SDK whatsoever, but Android does have a BluetoothSocket and BluetoothServerSocket for TCP connections.
This article, http://blog.moritzhaarmann.de/blog/2014/04/27/sorry-state-of-p2p/ written in 2014, suggest it is possible via Bluetooth LE. Available in Android 4.3+ and iOS6+
Two issues:
According to the Android Dashboard only around 30 percent of Android devices support Bluetooth LE https://developer.android.com/about/dashboards/index.html?utm_source=ausdroid.net
Communication between Android-to-Android must be done using some other method (which is not a big problem) because Android devices cannot act as server for B LE connections.
Bounjour on the iPhone gives you full access to all of the Bluetooth protocols, so you don't have to use GameKit. As for when someone will provide an easy to use iPhone to Android GameKit like framework - hard to tell.
An iPhone can already talk to any other Bluetooth device using Bonjour today.
-t
It is absolutely possible! In fact I am amazed that more people haven't done it!
Theory:
Bluetooth is just a wireless socket that you push data across and it comes across the other side, just like tcp/ip.
Practice:
http://www.techcrunch.com/2009/11/11/bump-goes-cross-platform-with-new-android-app-upgrades-iphone-version-too/
Better yet, Bump is cross-platform, which means that you can bump an Android phone with an iPhone and it should work seamlessly.
I am looking to develop an iPhone application that will require point-to-point WiFi communications on an iPhone. I would like to use the WiFi interface and have the application stream between the phone and a WiFi device. Does anyone have some experience with this? Is it even possible? I know there is a discovery application but I am looking for something a little more robust.
As far as I know (as the SDK stands now), the only thing available is communication over the existing network connection. The SDK doesn't allow for setting up wireless network connections, or creating ad-hoc networks. I believe the only way to join or create wifi networks is through the settings app.