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I bought the phone which has android 4.4 version and i am using ubuntu 12.04 and i am unable to connect this to my PC.
Please post details about the issue.
Android devices use MTP (Media Transfer Protocol) file transfer system. So, in order to mount your device on Ubuntu, you need MTP file system package installed. Using MTP is kind of tricky. And it's unstable for newer android versions. So using Go-mtpfs seems better in order to mount Android 4.0+ devices.
I was facing the same problem with my android device. But Go-mtpfs has solved the issue for me.
I hope it works for you as well.