How to mount an Android Jelly Bean phone if there's no option?

Install go-mtpfs from WebUpd8 repository following this guide:

http://www.webupd8.org/2012/12/how-to-mount-android-40-ubuntu-go-mtpfs.html

Then add go-mtpfs-unity.desktop the dash, connect your phone via usb and you have a quicklist to mount and dismount your android device.

Sorry for my bad English, I speak Spanish.

I have had the same problem with my Samsung Captivate Glide. In my opinion, not the perfect fix, but an option is an app "USB mode switch for SGS1 on CM" I got from the Play store. Worth a look.

There is now a new, even smoother, method to achieve this using back-ported packages from Ubuntu 13.04. Please follow the guide from WebUpd8:

http://www.webupd8.org/2013/01/upgrade-to-gvfs-with-mtp-support-in.html