How can I send simple data from an iPhone to another iPhone, or an Android?

Question

I'm just getting started with mobile development, and after considerable searching I'm still confused about sending a message from my iPhone to another or an Android. For instance, in building a simple Tic-Tac-Toe game, if I want to notify the other phone of a move, what is the best way to do so? Wifi, bluetooth, 3G? And how?

Many methods seem to point to communicating through a web server, but I'd rather send them directly from phone to phone if possible. (this is for native apps of course)

Answer 1

As far as i know does the iphone only support incoming messages over push notifications. This means, that you have to update the information, by requesting it from web services etc. The bluetooth API of the iphone doesn't support this either.

Answer 2

If you don't want to have a server (or even if you do! It depends!) it sounds like you will want to use TCP sockets. Apple doesn't have a generic bluetooth API to use with iPhone-to-android communication and you'll have TCP access anyway with 3G. A 3G network connection is very similar to wifi and you should be able to check for the difference as needed with little change to your overall networking code. I'm not sure if bonjour is supported on android, but I bet someone has ported it for similar reasons already, and it is supported in iOS. Apple has a networking section for iOS that you may find informative.

Additionally if you want to stay within the iOS device only realm you could use GameKit to communicate via bluetooth.

Hope that helps some.

Answer 3

WiFi is not always there - by limiting your users' options to areas with access points, you'll lose sales. Not sure about Bluetooth - how prevalent is it on handsets, how much of the API is exposed. Your best bet, IMHO, is 3G. With some kind of a central presence server (Web or otherwise), with optional proxying. Read up on peer-to-peer networking.

Answer 4

The easiest way is to create a web server with an API and the clients poll the server for new moves (or the server pushes the client an update). This is the only way you're going to be able to do it over 3G unless you can figure out the IP addresses of both phones (do phones even keep the same IP address for a long period of time?) and open up sockets between them and let one phone be the server and the other be the client (could cause potential cheating).