If you do any Android development in Ubuntu it is much better to test your android application on a real device rather than just relying on the emulator.
There are following steps to attach your Android device to Ubuntu :
Now :

As Shown in Image Bus 002 Device 021: ID 0bb4:0c8b High Tech Computer Corp.
In this Vender ID is "0bb4" and Product Id is "0c8b" .
Now :
create/edit file /etc/udev/rules.d/51-android.rules
Then enter your log in password.
Now a File will open and wirte in file :
Change Your Vender Id and Product id.
and Save & close File 51-android.rules.
Now run these commands.
There are following steps to attach your Android device to Ubuntu :
$
/path of adb/adb devices
List of devices attached
???????????? no permissions
Now :
$ lsusb

As Shown in Image Bus 002 Device 021: ID 0bb4:0c8b High Tech Computer Corp.
In this Vender ID is "0bb4" and Product Id is "0c8b" .
Now :
create/edit file /etc/udev/rules.d/51-android.rules
$sudo gedit /etc/udev/rules.d/51-android.rules
Then enter your log in password.
Now a File will open and wirte in file :
SUBSYSTEMS==”usb”, ATTRS{idVendor}==”0bb4″, ATTRS{idProduct}==”0c8b″, MODE=”0666″
Change Your Vender Id and Product id.
and Save & close File 51-android.rules.
Now run these commands.
$ sudo restart udev
$ /path of adb/adb devices
$ /path of adb/adb kill-server
$ /path of adb/adb start-server