diff --git a/persoconf/main.py b/persoconf/main.py
index fdf0109..9084e78 100755
--- a/persoconf/main.py
+++ b/persoconf/main.py
@@ -237,6 +237,7 @@ parser_update = subparsers.add_parser( "update",
 
 parser_update.add_argument( "app",
                             type=str,
+                            nargs="?",
                             help="The app to update" )
 
 parser_update.add_argument( "files",
@@ -427,56 +428,105 @@ if args.command == "add":
 ########################################
 if args.command == "update":
 
-    # TODO app == None => update all apps
-    # Load app META file
-    try:
-        appmeta = Metafile(json_path = "/".join([persoconf.path, args.app, persoconf.metafile]))
+    # app == None => update all apps
+    apps_to_update = {}
+    if args.app is None:
+        apps_to_update = persoconf.list_apps(logger=log)
 
-    except FileNotFoundError:
-        log.info("Metafile %s does not exist for app %s" % (persoconf.metafile, args.app))
-        appmeta = Metafile( name=args.app )
-        appmeta.json_path = "/".join( [persoconf.path, args.app, persoconf.metafile] )
-
-    except MalformedMetafileError:
-        log.error("Malformed metafile %s in app %s" % (persoconf.metafile, args.app) )
-        exit(1)
-
-    # TODO check that the app exists
-
-    # The filenames can be confnames or real files names. For each we'll assume
-    # first that it's a confname, then that it's a file name if that fails.
-    if args.files != []:
-
-        dstdic = appmeta.get_files_dst2src()
-
-        for f in args.files:
-            # It's probably a confname
-            if f in appmeta.files:
-                if copy_file_or_directory(log, path_dst='/'.join([persoconf.path, args.app, f]), path_src=appmeta.files[f]["dest"]):
-                    log.info("Updated %s from %s" % (f, appmeta.files[f]["dest"]))
-                else:
-                    log.warning("Failed to update %s from %s ; ignoring" % (f, appmeta.files[f]["dest"]))
-
-            # If not, it must be a real filename
-            else:
-                absf = contractuser( os.path.abspath(os.path.expanduser(f)) )
-                if absf in dstdic:
-                    if copy_file_or_directory(log, path_dst='/'.join([persoconf.path, args.app, dstdic[absf]]), path_src=absf):
-                        log.info("Updated %s from %s" % (dstdic[absf], absf))
-                    else:
-                        log.warning("Failed to update %s from %s ; ignoring" % (dstdic[absf], absf))
-
-                # Otherwise, it's nothing.
-                else:
-                    log.warning("Cannot find file %s in app data; ignoring it")
-
-    # If they were no 'file' args, it means we need to update all files in the app
     else:
-        for f in appmeta.files:
-            if copy_file_or_directory(log, path_dst='/'.join([persoconf.path, args.app, f]), path_src=appmeta.files[f]["dest"]):
-                log.info("Updated %s from %s" % (f, appmeta.files[f]["dest"]))
-            else:
-                log.warning("Failed to update %s from %s ; ignoring" % (f, appmeta.files[f]["dest"]))
+        try:
+            appmeta = Metafile( json_path = persoconf.path +"/"+
+                                            args.app       +"/"+
+                                            persoconf.metafile )
+
+            apps_to_update[appmeta.name] = appmeta
+
+        except FileNotFoundError:
+            log.error( "Metafile %s does not exist for app %s"
+                       % (persoconf.metafile, args.app) )
+            exit(1)
+
+        except MalformedMetafileError:
+            log.error( "Malformed metafile %s in app %s"
+                       % (persoconf.metafile, args.app) )
+            exit(1)
+
+
+    for app in apps_to_update:
+
+        if args.files != []:
+
+            dstdic = apps_to_update[app].get_files_dst2src()
+
+            # The filenames can be confnames or real files names. For each
+            # we'll assume first that it's a confname, then that it's a file
+            # name if that fails.
+            for f in args.files:
+
+                # 1) It's probably a confname
+                if f in apps_to_update[app].files:
+
+                    if copy_file_or_directory(
+                            log                                 ,
+                            path_dst =       persoconf.path
+                                       +"/"+ app
+                                       +"/"+ f                  ,
+                            path_src = apps_to_update[app].files[f]["dest"]
+                            ):
+
+                        log.info( "Updated %s from %s"
+                                  % (f, apps_to_update[app].files[f]["dest"]) )
+                    else:
+                        log.warning(
+                                "Failed to update %s from %s ; ignoring"
+                                % ( f, apps_to_update[app].files[f]["dest"])
+                                )
+
+                # 2) If not, it must be a real filename
+                else:
+
+                    absf = contractuser(os.path.abspath(os.path.expanduser(f)))
+                    if absf in dstdic:
+
+                        if copy_file_or_directory(
+                                log                              ,
+                                path_dst =       persoconf.path
+                                           +"/"+ app
+                                           +"/"+ dstdic[absf]    ,
+                                path_src = absf
+                                ):
+                            log.info( "Updated %s from %s"
+                                      % (dstdic[absf], absf) )
+
+                        else:
+                            log.warning( "Failed to update %s from %s ; "     \
+                                         "ignoring"
+                                         % (dstdic[absf], absf) )
+
+                    # 3) Otherwise, no idea what it is
+                    else:
+                        log.warning( "Cannot find file %s in app data; "      \
+                                     "ignoring it"
+                                     % f )
+
+        # If they were no 'file' args, it means we need to update all files in
+        # the app
+        else:
+
+            for f in apps_to_update[app].files:
+                if copy_file_or_directory(
+                        log                                 ,
+                        path_dst =       persoconf.path
+                                   +"/"+  app
+                                   +"/"+  f                 ,
+                        path_src = apps_to_update[app].files[f]["dest"]
+                        ):
+                    log.info( "Updated %s from %s"
+                            % (f, apps_to_update[app].files[f]["dest"]) )
+
+                else:
+                    log.warning( "Failed to update %s from %s ; ignoring"
+                                 % (f, apps_to_update[app].files[f]["dest"]) )
 
 # PACKAGE COMMAND
 ########################################