diff --git a/src/calibre/library/server/content.py b/src/calibre/library/server/content.py
index 0c0405aa50..c9ffe83f45 100644
--- a/src/calibre/library/server/content.py
+++ b/src/calibre/library/server/content.py
@@ -252,10 +252,14 @@ class ContentServer(object):
         cherrypy.response.headers['Content-Length'] = fmt.tell()
         fmt.seek(0)
 
+        ua = cherrypy.request.headers.get('User-Agent', '').strip()
+        have_kobo_browser = self.is_kobo_browser(ua)
+        file_extension = "kepub.epub" if format.lower() == "kepub" and have_kobo_browser else format
+
         au = authors_to_string(newmi.authors if newmi.authors else
                 [_('Unknown')])
         title = newmi.title if newmi.title else _('Unknown')
-        fname = u'%s - %s_%s.%s'%(title[:30], au[:30], id, format.lower())
+        fname = u'%s - %s_%s.%s'%(title[:30], au[:30], id, file_extension.lower())
         fname = ascii_filename(fname).replace('"', '_')
         cherrypy.response.headers['Content-Disposition'] = \
                 b'attachment; filename="%s"'%fname
diff --git a/src/calibre/library/server/mobile.py b/src/calibre/library/server/mobile.py
index 1b6479250e..b4590b2d3d 100644
--- a/src/calibre/library/server/mobile.py
+++ b/src/calibre/library/server/mobile.py
@@ -92,7 +92,7 @@ def build_navigation(start, num, total, url_base):  # {{{
     # }}}
 
 def build_index(books, num, search, sort, order, start, total, url_base, CKEYS,
-        prefix):
+        prefix, have_kobo_browser=False):
     logo = DIV(IMG(src=prefix+'/static/calibre.png', alt=__appname__), id='logo')
 
     search_box = build_search_box(num, search, sort, order, prefix)
@@ -122,13 +122,14 @@ def build_index(books, num, search, sort, order, start, total, url_base, CKEYS,
         for fmt in book['formats'].split(','):
             if not fmt or fmt.lower().startswith('original_'):
                 continue
+            file_extension = "kepub.epub" if fmt.lower() == "kepub" and have_kobo_browser else fmt
             a = quote(ascii_filename(book['authors']))
             t = quote(ascii_filename(book['title']))
             s = SPAN(
                 A(
                     fmt.lower(),
                     href=prefix+'/get/%s/%s-%s_%d.%s' % (fmt, a, t,
-                        book['id'], fmt.lower())
+                        book['id'], file_extension.lower())
                 ),
                 CLASS('button'))
             s.tail = u''
@@ -182,11 +183,16 @@ class MobileServer(object):
     'A view optimized for browsers in mobile devices'
 
     MOBILE_UA = re.compile('(?i)(?:iPhone|Opera Mini|NetFront|webOS|Mobile|Android|imode|DoCoMo|Minimo|Blackberry|MIDP|Symbian|HD2|Kindle)')
+    KOBO_UA = re.compile('(?i)(?:Kobo Touch)')
 
     def is_mobile_browser(self, ua):
         match = self.MOBILE_UA.search(ua)
         return match is not None and 'iPad' not in ua
 
+    def is_kobo_browser(self, ua):
+        match = self.KOBO_UA.search(ua)
+        return match is not None
+
     def add_routes(self, connect):
         connect('mobile', '/mobile', self.mobile)
         connect('mobile_css', '/mobile/style.css', self.mobile_css)
@@ -282,10 +288,13 @@ class MobileServer(object):
         cherrypy.response.headers['Last-Modified'] = self.last_modified(updated)
 
         url_base = "/mobile?search=" + search+";order="+order+";sort="+sort+";num="+str(num)
+        ua = cherrypy.request.headers.get('User-Agent', '').strip()
+        have_kobo_browser = self.is_kobo_browser(ua)
 
         raw = html.tostring(build_index(books, num, search, sort, order,
                              start, len(ids), url_base, CKEYS,
-                             self.opts.url_prefix),
+                             self.opts.url_prefix,
+                             have_kobo_browser=have_kobo_browser),
                              encoding='utf-8',
                              pretty_print=True)
         # tostring's include_meta_content_type is broken