It's using multicasts to find other clients within the same WiFi network.
So no setup ist needed.
In addition to the Android app there is also a Java based PC client available.
This client has been tested on Linux and Windows but might work on other configurations.
The full description and a short video can be found on the Android Market page:
You can not only transfer files between PC and Android but also between Android devices.
This is beta software, so there are still bugs.
Please report them in this thread. I'll have a look as soon as I find time and will contact some of you to get things fixed.
There are surely some timing (and timeout) problems which need some attention.
Make sure your router supports multicasts.
Please post comments, I'll try to read them all
Link to PC client
Copying of directories
Supported since 0.8.4 beta.
Testing and how you can help
To test if your network is able to deal with multicast messages you can do the following test:
1. Download the file MulticastSender.jar and MulticastReceiver.jar.
2. On one PC start the MulticastSender.jar and on another the MulticastReceiver.jar.
The sender sends screenshots. If you see the screenshots on the receiver's side, multicasts are working for you.
If not, X-Link will not work.
If this works but X-Link doesn't it's likely that there is a problem concerning timeouts within X-Link.
In this case, please send me a mail (xlink [at] fun2code.de).
If sharing on Android does not work
Sharing does not seem to be working in some apps.
If you encounter such a problem, please download the app XLinkDebug.apk and install it.
Use sharing as you normally would with X-Link but select X-Link Debug instead.
On execution the app will copy the information needed for me to fix the issue to the clipboard.
Please paste the clipboard into a mail ans send it to the following address: xlink [at] fun2code.de