adb logcat hangs with "waiting for device" message

Here is yet another potential method to solve this -- in the past, the above solutions will work, but in my case, this time, this was the thing that fixed it:

1. Plug device into USB
2. Settings -> Developer Options
3. Revoke USB Debugging Authorization
4. Unplug Device
5. Repeat Step 1
6. Authorize Device
7. Repeat Steps 4&5

adb devices should now show device

adb logcat should now output logs from device

I am not pretty much sure if this works for you but can you please try the steps below:

# Kill and restart      
$ adb kill-server      
$ adb start-server     
 daemon not running. starting it now *      
 daemon started successfully *         

# Device appears, but is listed as offline

$ adb devices      
$ adb logcat

I had this same problem on Ubuntu 12.04. Thankfully MickeyMicro had the solution that worked for me:

1. Run the command: gksudo gedit /etc/udev/rules.d/51-android.rules

2. Add the following line to the blank file

SUBSYSTEM=="usb", ATTR{idVendor}="2080", MODE="0666" (I used this one on 12.04)

SUBSYSTEM=="usb", SYSFS{idVendor}="2080", MODE="0666" (Another recommended for 10.04)

1. Save and close gedit.

2. Run the command: sudo chmod a+rx /etc/udev/rules.d/51-android.rules

3. Restart the system.

4. Run the command: sudo sh -c "mkdir -p ~/.android; echo 0x2080 > ~/.android/adb_usb.ini; adb kill-server; adb devices"

5. Verify that you have permissions to access the device. adb devices should return normal response, rather than a "???????????? no permissions" message.

http://forum.cyanogenmod.com/topic/23163-need-help-for-adb-connection-on-ubuntu/

I have also experienced similar problems I think I solved it by having the USB debugging option switched on within Developer Options in Settings.

REPEAT The following steps above, it should work!