diff --git a/src/calibre/devices/android/driver.py b/src/calibre/devices/android/driver.py
index 9e8aa5fe17..efe979158d 100644
--- a/src/calibre/devices/android/driver.py
+++ b/src/calibre/devices/android/driver.py
@@ -186,10 +186,15 @@ class ANDROID(USBMS):
             }
     EBOOK_DIR_MAIN = ['eBooks/import', 'wordplayer/calibretransfer', 'Books',
             'sdcard/ebooks']
-    EXTRA_CUSTOMIZATION_MESSAGE = _('Comma separated list of directories to '
-            'send e-books to on the device. The first one that exists will '
+    EXTRA_CUSTOMIZATION_MESSAGE = [_('Comma separated list of directories to '
+            'send e-books to on the device\'s main memory. The first one that exists will '
+            'be used'),
+            _('Comma separated list of directories to '
+            'send e-books to on the device\'s storage cards. The first one that exists will '
             'be used')
-    EXTRA_CUSTOMIZATION_DEFAULT = ', '.join(EBOOK_DIR_MAIN)
+            ]
+
+    EXTRA_CUSTOMIZATION_DEFAULT = [', '.join(EBOOK_DIR_MAIN), '']
 
     VENDOR_NAME      = ['HTC', 'MOTOROLA', 'GOOGLE_', 'ANDROID', 'ACER',
             'GT-I5700', 'SAMSUNG', 'DELL', 'LINUX', 'GOOGLE', 'ARCHOS',
@@ -237,23 +242,35 @@ class ANDROID(USBMS):
 
     def post_open_callback(self):
         opts = self.settings()
-        dirs = opts.extra_customization
-        if not dirs:
-            dirs = self.EBOOK_DIR_MAIN
-        else:
-            dirs = [x.strip() for x in dirs.split(',')]
-        self.EBOOK_DIR_MAIN = dirs
+        opts = opts.extra_customization
+        if not opts:
+            opts = [self.EBOOK_DIR_MAIN, '']
+
+        def strtolist(x):
+            if isinstance(x, basestring):
+                x = [y.strip() for y in x.split(',')]
+            return x or []
+
+        opts = [strtolist(x) for x in opts]
+        self._android_main_ebook_dir = opts[0]
+        self._android_card_ebook_dir = opts[1]
 
     def get_main_ebook_dir(self, for_upload=False):
-        dirs = self.EBOOK_DIR_MAIN
+        dirs = self._android_main_ebook_dir
         if not for_upload:
             def aldiko_tweak(x):
                 return 'eBooks' if x == 'eBooks/import' else x
-            if isinstance(dirs, basestring):
-                dirs = [dirs]
             dirs = list(map(aldiko_tweak, dirs))
         return dirs
 
+    def get_carda_ebook_dir(self, for_upload=False):
+        if not for_upload:
+            return ''
+        return self._android_card_ebook_dir
+
+    def get_cardb_ebook_dir(self, for_upload=False):
+        return self.get_carda_ebook_dir()
+
     def windows_sort_drives(self, drives):
         try:
             vid, pid, bcd = self.device_being_opened[:3]
@@ -271,7 +288,8 @@ class ANDROID(USBMS):
         proxy = cls._configProxy()
         proxy['format_map'] = ['mobi', 'azw', 'azw1', 'azw4', 'pdf']
         proxy['use_subdirs'] = False
-        proxy['extra_customization'] = ','.join(['kindle']+cls.EBOOK_DIR_MAIN)
+        proxy['extra_customization'] = [
+                ','.join(['kindle']+cls.EBOOK_DIR_MAIN), '']
 
     @classmethod
     def configure_for_generic_epub_app(cls):
diff --git a/src/calibre/devices/usbms/device.py b/src/calibre/devices/usbms/device.py
index 4d4b198de0..025a7e2d95 100644
--- a/src/calibre/devices/usbms/device.py
+++ b/src/calibre/devices/usbms/device.py
@@ -991,24 +991,28 @@ class Device(DeviceConfig, DevicePlugin):
         elif on_card and on_card not in ('carda', 'cardb'):
             raise DeviceError(_('Selected slot: %s is not supported.') % on_card)
 
-        if on_card == 'carda':
-            path = os.path.join(self._card_a_prefix,
-                    *(self.get_carda_ebook_dir(for_upload=True).split('/')))
-        elif on_card == 'cardb':
-            path = os.path.join(self._card_b_prefix,
-                    *(self.EBOOK_DIR_CARD_B.split('/')))
-        else:
-            candidates = self.get_main_ebook_dir(for_upload=True)
+        def get_dest_dir(prefix, candidates):
             if isinstance(candidates, basestring):
                 candidates = [candidates]
+            if not candidates:
+                candidates = ['']
             candidates = [
-                    ((os.path.join(self._main_prefix, *(x.split('/')))) if x else
-                    self._main_prefix) for x
-                    in candidates]
+                ((os.path.join(prefix, *(x.split('/')))) if x else prefix)
+                for x in candidates]
             existing = [x for x in candidates if os.path.exists(x)]
             if not existing:
-                existing = candidates[:1]
-            path = existing[0]
+                existing = candidates
+            return existing[0]
+
+        if on_card == 'carda':
+            candidates = self.get_carda_ebook_dir(for_upload=True)
+            path = get_dest_dir(self._carda_prefix, candidates)
+        elif on_card == 'cardb':
+            candidates = self.get_cardb_ebook_dir(for_upload=True)
+            path = get_dest_dir(self._cardb_prefix, candidates)
+        else:
+            candidates = self.get_main_ebook_dir(for_upload=True)
+            path = get_dest_dir(self._main_prefix, candidates)
 
         def get_size(obj):
             path = getattr(obj, 'name', obj)