Hello Johannes,
I made some modifications on the code, trying to display the bundle payload content on the main activity, but it didn't work as I expected. The idea is to send a bundle from the first mobile to a second, and the second gets this bundle, open it's payload and display it. I thought I needed only to call a method inside the public void payload(byte[] data) method, sending it's content to the interface. But the fact is, it was displaying the echoed bundle. For example, the first mobile sent a bundle to a second with echo, the second sent it back, and then on the first mobile, it entered the payload method and displayed. When I removed the /echo, this stopped working and the second mobile continued without displaying it. What exactly do I need to change, to make the second mobile receive a bundle and extract the payload information?