Comment 2 for bug 903422

That isn't true that "Android 4 will not support anymore usb mass-storage protocol" it is up to device maker to provide sdcard slots or "internal sdcard". In that case mass storage will be available.

But more devices do not have sdcard support or sdcard like internal memory. So, those are only accessible using the MTP protocol which needs to be implemented in GVFS to automatically mount in .gvfs users folders.