--- /usr/sbin/univention-upgrade.bak	2015-07-13 12:31:34.499392000 +0200
+++ /usr/sbin/univention-upgrade	2015-07-13 13:10:08.779392000 +0200
@@ -37,6 +37,7 @@
 import optparse
 import subprocess
 import traceback
+import logging
 
 import univention.config_registry
 
@@ -271,6 +272,68 @@
 		else:
 			dprint(silent, 'none')
 
+		#######################################################################
+		# APP UPDATE
+		#######################################################################
+		try:
+			from univention.appcenter.actions import get_action
+			import univention.appcenter.log as appcenter_log
+			from argparse import Namespace
+			app_upgrade = get_action('upgrade')
+			if app_upgrade is None:
+				raise ImportError()
+		except ImportError:
+			# the new univention.appcenter package is not installed. nevermind
+			# cannot be a dependency as the app center depends on updater...
+			pass
+		else:
+			# check if component updates are available
+			dprint(silent, 'Checking for app updates: ', newline=False)
+			app_upgrade = app_upgrade()
+			appcenter_log.log_to_logfile()
+			appcenter_log._reverse_umc_module_logger()
+
+			# own logging
+			handler = logging.FileHandler(LOGFN)
+			appcenter_log.get_base_logger().addHandler(handler)
+			logger = logging.getLogger('univention.appcenter.actions.upgrade.readme')
+			handler = logging.StreamHandler(sys.stdout)
+			handler.setLevel(logging.INFO)
+			logger.addHandler(handler)
+
+			new_apps = list(app_upgrade.iter_upgradable_apps())
+			update_available = bool(new_apps)
+
+			if update_available:
+				# updates available ==> stop here in "check-mode"
+				if checkForUpdates:
+					dprint(silent, 'found')
+					return True
+
+				dprint(silent, 'found\n')
+				dprint(silent, 'The following apps can be updated:\n')
+				for app in new_apps:
+					dprint(silent, '%(name)s: Version %(old)s can be updated to %(new)s' % {'name': app.name, 'old': app.version, 'new': app.candidate.version})
+				dprint(silent, 'Starting univention-app update at %s...' % (time.ctime()), debug=True)
+				dprint(silent, '\nStarting app update', newline=False)
+				success = True
+				for app in new_apps:
+					if interactive:
+						run_app = readcontinue('\nDo you want to update %s [Y|n]?' % app.name)
+					if run_app:
+						time.sleep(1)
+
+						success = app_upgrade.call(app=app, noninteractive=not interactive) and success
+
+				if not success:
+					dprint(silent, 'ERROR: app upgrade failed. Please check /var/log/univention/updater.log\n')
+					sys.exit(1)
+				dprint(silent, 'univention-app upgrade finished at %s...' % (time.ctime()), debug=True)
+				dprint(silent, 'done')
+				time.sleep(1)
+			else:
+				dprint(silent, 'none')
+
 	# updates available ==> stop here in "check-mode"
 	if checkForUpdates:
 		return False