diff --git a/src/calibre/devices/android/driver.py b/src/calibre/devices/android/driver.py
index d26489c42f..a12f37c7eb 100644
--- a/src/calibre/devices/android/driver.py
+++ b/src/calibre/devices/android/driver.py
@@ -128,7 +128,7 @@ class ANDROID(USBMS):
             '7', 'A956', 'A955', 'A43', 'ANDROID_PLATFORM', 'TEGRA_2',
             'MB860', 'MULTI-CARD', 'MID7015A', 'INCREDIBLE', 'A7EB', 'STREAK',
             'MB525', 'ANDROID2.3', 'SGH-I997', 'GT-I5800_CARD', 'MB612',
-            'GT-S5830_CARD']
+            'GT-S5830_CARD', 'GT-S5570_CARD']
     WINDOWS_CARD_A_MEM = ['ANDROID_PHONE', 'GT-I9000_CARD', 'SGH-I897',
             'FILE-STOR_GADGET', 'SGH-T959', 'SAMSUNG_ANDROID', 'GT-P1000_CARD',
             'A70S', 'A101IT', '7', 'INCREDIBLE', 'A7EB', 'SGH-T849_CARD',
diff --git a/src/calibre/ebooks/mobi/debug.py b/src/calibre/ebooks/mobi/debug.py
index b6c7991739..514cf9c246 100644
--- a/src/calibre/ebooks/mobi/debug.py
+++ b/src/calibre/ebooks/mobi/debug.py
@@ -638,7 +638,7 @@ class IndexEntry(object): # {{{
                     self.tags.append(Tag(aut_tag[0], [val], self.entry_type,
                         cncx))
 
-        if raw.replace(b'\x00', b''):
+        if raw.replace(b'\x00', b''): # There can be padding null bytes
             raise ValueError('Extra bytes in INDX table entry %d: %r'%(self.index, raw))
 
     @property
@@ -736,6 +736,9 @@ class IndexRecord(object): # {{{
         for i in range(self.idxt_count):
             off, = u(b'>H', indices[i*2:(i+1)*2])
             self.index_offsets.append(off-192)
+        rest = indices[(i+1)*2:]
+        if rest.replace(b'\0', ''): # There can be padding null bytes
+            raise ValueError('Extra bytes after IDXT table: %r'%rest)
 
         indxt = raw[192:self.idxt_offset]
         self.indices = []
@@ -772,7 +775,7 @@ class IndexRecord(object): # {{{
                 len(w), not bool(w.replace(b'\0', b'')) ))
         a('Header length: %d'%self.header_length)
         u(self.unknown1)
-        a('Header Type: %d'%self.header_type)
+        a('Unknown (header type? index record number? always 1?): %d'%self.header_type)
         u(self.unknown2)
         a('IDXT Offset: %d'%self.idxt_offset)
         a('IDXT Count: %d'%self.idxt_count)
diff --git a/src/calibre/ebooks/mobi/writer2/indexer.py b/src/calibre/ebooks/mobi/writer2/indexer.py
index 2296a40d14..48b1d82c04 100644
--- a/src/calibre/ebooks/mobi/writer2/indexer.py
+++ b/src/calibre/ebooks/mobi/writer2/indexer.py
@@ -173,10 +173,52 @@ class Indexer(object):
 
         if self.is_periodical:
             indices = self.create_periodical_index()
-            indices
         else:
             raise NotImplementedError()
 
+        self.records.append(self.create_index_record(indices))
+
+    def create_index_record(self, indices):
+        header_length = 192
+        buf = StringIO()
+
+        # Write index entries
+        offsets = []
+        for i in indices:
+            offsets.append(buf.tell())
+            buf.write(i.bytestring)
+        index_block = align_block(buf.getvalue())
+
+        # Write offsets to index entries as an IDXT block
+        idxt_block = b'IDXT'
+        buf.truncate(0)
+        for offset in offsets:
+            buf.write(pack(b'>H', header_length+offset))
+        idxt_block = align_block(idxt_block + buf.getvalue())
+        body = index_block + idxt_block
+
+        header = b'INDX'
+        buf.truncate(0)
+        buf.write(pack(b'>I', header_length))
+        buf.write(b'\0'*4) # Unknown
+        buf.write(pack(b'>I', 1)) # Header type? Or index record number?
+        buf.write(b'\0'*4) # Unknown
+        # IDXT block offset
+        buf.write(pack(b'>I', header_length + len(index_block)))
+        # Number of index entries
+        buf.write(pack(b'>I', len(offsets)))
+        # Unknown
+        buf.write(b'\xff'*8)
+        # Unknown
+        buf.write(b'\0'*156)
+
+        header += buf.getvalue()
+
+        ans = header + body
+        if len(ans) > 0x10000:
+            raise ValueError('Too many entries (%d) in the TOC'%len(offsets))
+        return ans
+
     def create_periodical_index(self): # {{{
         periodical_node = iter(self.oeb.toc).next()
         periodical_node_offset = self.serializer.body_start_offset
diff --git a/src/calibre/gui2/book_details.py b/src/calibre/gui2/book_details.py
index ebb7c9d5ed..c65b6b5d14 100644
--- a/src/calibre/gui2/book_details.py
+++ b/src/calibre/gui2/book_details.py
@@ -133,6 +133,7 @@ def render_data(mi, use_roman_numbers=True, all_fields=False):
             authors = []
             formatter = EvalFormatter()
             for aut in mi.authors:
+                link = ''
                 if mi.author_link_map[aut]:
                     link = mi.author_link_map[aut]
                 elif gprefs.get('default_author_link'):
@@ -143,8 +144,6 @@ def render_data(mi, use_roman_numbers=True, all_fields=False):
                         vals['author_sort'] = aut.replace(' ', '+')
                     link = formatter.safe_format(
                             gprefs.get('default_author_link'), vals, '', vals)
-                else:
-                    link = ''
                 if link:
                     link = prepare_string_for_xml(link)
                     authors.append(u'<a href="%s">%s</a>'%(link, aut))