diff --git a/plinth/app.py b/plinth/app.py
index bb519d7f8..c3d388c44 100644
--- a/plinth/app.py
+++ b/plinth/app.py
@@ -5,6 +5,8 @@ Base class for all Freedombox applications.
 
 import collections
 
+from . import clients as clients_module
+
 
 class App:
     """Implement common functionality for an app.
@@ -373,3 +375,5 @@ class Info(FollowerComponent):
         self.manual_page = manual_page
         self.clients = clients
         self.donation_url = donation_url
+        if clients:
+            clients_module.validate(clients)
diff --git a/plinth/modules/bepasty/manifest.py b/plinth/modules/bepasty/manifest.py
index f61f96a81..1d5873a41 100644
--- a/plinth/modules/bepasty/manifest.py
+++ b/plinth/modules/bepasty/manifest.py
@@ -2,15 +2,13 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('bepasty'),
     'platforms': [{
         'type': 'web',
         'url': '/bepasty'
     }]
-}])
+}]
 
 backup = {
     'config': {
diff --git a/plinth/modules/calibre/manifest.py b/plinth/modules/calibre/manifest.py
index dde545875..85dcee040 100644
--- a/plinth/modules/calibre/manifest.py
+++ b/plinth/modules/calibre/manifest.py
@@ -2,15 +2,13 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('calibre'),
     'platforms': [{
         'type': 'web',
         'url': '/calibre/'
     }]
-}])
+}]
 
 backup = {
     'data': {
diff --git a/plinth/modules/cockpit/manifest.py b/plinth/modules/cockpit/manifest.py
index a0d873945..db8953a66 100644
--- a/plinth/modules/cockpit/manifest.py
+++ b/plinth/modules/cockpit/manifest.py
@@ -5,15 +5,13 @@ Application manifest for cockpit.
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('Cockpit'),
     'platforms': [{
         'type': 'web',
         'url': '/_cockpit/'
     }]
-}])
+}]
 
 # cockpit.conf need not be backed up because add/remove domain signals are
 # triggered on every Plinth domain change (and cockpit application install) and
diff --git a/plinth/modules/deluge/manifest.py b/plinth/modules/deluge/manifest.py
index da06256a4..8d6241785 100644
--- a/plinth/modules/deluge/manifest.py
+++ b/plinth/modules/deluge/manifest.py
@@ -2,16 +2,14 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('Deluge'),
     'description': _('Bittorrent client written in Python/PyGTK'),
     'platforms': [{
         'type': 'web',
         'url': '/deluge'
     }]
-}])
+}]
 
 backup = {
     'config': {
diff --git a/plinth/modules/diaspora/manifest.py b/plinth/modules/diaspora/manifest.py
index b44ecae9c..02b0efdc7 100644
--- a/plinth/modules/diaspora/manifest.py
+++ b/plinth/modules/diaspora/manifest.py
@@ -2,11 +2,11 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 from plinth.modules import diaspora
 from plinth.utils import format_lazy
 
-clients = validate([{
+clients = [{
     'name':
         _('dandelion*'),
     'description':
@@ -30,4 +30,4 @@ clients = validate([{
                 host=diaspora.get_configured_domain_name()
                 if diaspora.is_setup() else "<please-setup-domain-name>")
     }]
-}])
+}]
diff --git a/plinth/modules/ejabberd/manifest.py b/plinth/modules/ejabberd/manifest.py
index eff22e9b7..c1006331c 100644
--- a/plinth/modules/ejabberd/manifest.py
+++ b/plinth/modules/ejabberd/manifest.py
@@ -2,10 +2,10 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 from plinth.modules.jsxc import manifest as jsxc_manifest
 
-_clients = validate([{
+_clients = [{
     'name':
         _('Conversations'),
     'platforms': [{
@@ -99,7 +99,7 @@ _clients = validate([{
         'os': 'windows',
         'url': 'https://gajim.org/downloads.php'
     }]
-}])
+}]
 
 _clients.extend(jsxc_manifest.clients)
 
diff --git a/plinth/modules/gitweb/manifest.py b/plinth/modules/gitweb/manifest.py
index 08dc4e6d9..f37c347e9 100644
--- a/plinth/modules/gitweb/manifest.py
+++ b/plinth/modules/gitweb/manifest.py
@@ -2,12 +2,10 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
 CONFIG_FILE = '/etc/gitweb-freedombox.conf'
 GIT_REPO_PATH = '/var/lib/git'
 
-clients = validate([
+clients = [
     {
         'name': _('Gitweb'),
         'platforms': [{
@@ -32,7 +30,7 @@ clients = validate([
             'url': 'https://git-scm.com/download/windows'
         }]
     },
-])
+]
 
 backup = {
     'config': {
diff --git a/plinth/modules/i2p/manifest.py b/plinth/modules/i2p/manifest.py
index e631bf8af..335fbea7f 100644
--- a/plinth/modules/i2p/manifest.py
+++ b/plinth/modules/i2p/manifest.py
@@ -5,12 +5,10 @@ Application manifest for I2P.
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
 _package_id = 'net.geti2p.i2p'
 _download_url = 'https://geti2p.net/download'
 
-clients = validate([{
+clients = [{
     'name':
         _('I2P'),
     'platforms': [{
@@ -33,7 +31,7 @@ clients = validate([{
         'os': 'windows',
         'url': _download_url,
     }]
-}])
+}]
 
 backup = {
     'secrets': {
diff --git a/plinth/modules/ikiwiki/manifest.py b/plinth/modules/ikiwiki/manifest.py
index 69773651b..e2e4b82c7 100644
--- a/plinth/modules/ikiwiki/manifest.py
+++ b/plinth/modules/ikiwiki/manifest.py
@@ -2,14 +2,12 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('ikiwiki'),
     'platforms': [{
         'type': 'web',
         'url': '/ikiwiki'
     }]
-}])
+}]
 
 backup = {'data': {'directories': ['/var/lib/ikiwiki/', '/var/www/ikiwiki/']}}
diff --git a/plinth/modules/infinoted/manifest.py b/plinth/modules/infinoted/manifest.py
index daf1d4b15..a9e89364c 100644
--- a/plinth/modules/infinoted/manifest.py
+++ b/plinth/modules/infinoted/manifest.py
@@ -3,10 +3,9 @@
 from django.utils.translation import ugettext_lazy as _
 
 from plinth import cfg
-from plinth.clients import validate
 from plinth.utils import format_lazy
 
-clients = validate([{
+clients = [{
     'name':
         _('Gobby'),
     'description':
@@ -29,7 +28,7 @@ clients = validate([{
         'format': 'deb',
         'name': 'gobby'
     }]
-}])
+}]
 
 backup = {
     'data': {
diff --git a/plinth/modules/jsxc/manifest.py b/plinth/modules/jsxc/manifest.py
index 2bb8c46b6..c1b5f1e8e 100644
--- a/plinth/modules/jsxc/manifest.py
+++ b/plinth/modules/jsxc/manifest.py
@@ -3,14 +3,12 @@
 from django.urls import reverse_lazy
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('JSXC'),
     'platforms': [{
         'type': 'web',
         'url': reverse_lazy('jsxc:jsxc')
     }]
-}])
+}]
 
 backup = {}
diff --git a/plinth/modules/matrixsynapse/manifest.py b/plinth/modules/matrixsynapse/manifest.py
index dba665640..a9eb3f56c 100644
--- a/plinth/modules/matrixsynapse/manifest.py
+++ b/plinth/modules/matrixsynapse/manifest.py
@@ -2,12 +2,12 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
 _android_package_id = 'im.vector.app'
 _element_desktop_download_url = 'https://element.io/get-started'
 
-clients = validate([{
+clients = [{
     'name':
         _('Element'),
     'platforms': [{
@@ -41,7 +41,7 @@ clients = validate([{
         'os': 'windows',
         'url': _element_desktop_download_url,
     }]
-}])
+}]
 
 backup = {
     'config': {
diff --git a/plinth/modules/mediawiki/manifest.py b/plinth/modules/mediawiki/manifest.py
index a457ca908..1612300d4 100644
--- a/plinth/modules/mediawiki/manifest.py
+++ b/plinth/modules/mediawiki/manifest.py
@@ -2,15 +2,13 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('MediaWiki'),
     'platforms': [{
         'type': 'web',
         'url': '/mediawiki'
     }]
-}])
+}]
 
 backup = {
     'config': {
diff --git a/plinth/modules/minetest/manifest.py b/plinth/modules/minetest/manifest.py
index 039bc9478..f0fc23b7e 100644
--- a/plinth/modules/minetest/manifest.py
+++ b/plinth/modules/minetest/manifest.py
@@ -2,9 +2,9 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
-clients = validate([{
+clients = [{
     'name':
         _('Minetest'),
     'platforms': [{
@@ -34,7 +34,7 @@ clients = validate([{
         'format': 'deb',
         'name': 'minetest'
     }]
-}])
+}]
 
 backup = {
     'config': {
diff --git a/plinth/modules/minidlna/manifest.py b/plinth/modules/minidlna/manifest.py
index 55c233df3..1c9ae1945 100644
--- a/plinth/modules/minidlna/manifest.py
+++ b/plinth/modules/minidlna/manifest.py
@@ -2,9 +2,9 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
-clients = validate([
+clients = [
     {
         'name':
             _('vlc'),
@@ -96,7 +96,7 @@ clients = validate([
             'name': 'totem',
         }]
     },
-])
+]
 
 # TODO: get all media directories from config file
 # for now hard code default media folder.
diff --git a/plinth/modules/mldonkey/manifest.py b/plinth/modules/mldonkey/manifest.py
index 2240ae774..18280f0fc 100644
--- a/plinth/modules/mldonkey/manifest.py
+++ b/plinth/modules/mldonkey/manifest.py
@@ -5,9 +5,9 @@ Application manifest for mldonkey.
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
-clients = validate([{
+clients = [{
     'name': _('MLDonkey'),
     'platforms': [{
         'type': 'web',
@@ -34,7 +34,7 @@ clients = validate([{
         'store_name': 'google-play',
         'url': store_url('google-play', 'com.devwom.amldonkey'),
     }]
-}])
+}]
 
 backup = {
     'config': {
diff --git a/plinth/modules/mumble/manifest.py b/plinth/modules/mumble/manifest.py
index 79a702b7d..d99b6b53f 100644
--- a/plinth/modules/mumble/manifest.py
+++ b/plinth/modules/mumble/manifest.py
@@ -2,9 +2,9 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
-clients = validate([{
+clients = [{
     'name':
         _('Mumble'),
     'platforms': [{
@@ -52,7 +52,7 @@ clients = validate([{
         'store_name': 'google-play',
         'url': store_url('google-play', 'se.lublin.mumla')
     }]
-}])
+}]
 
 backup = {
     'data': {
diff --git a/plinth/modules/openvpn/manifest.py b/plinth/modules/openvpn/manifest.py
index 88d3c0b74..9a15acc11 100644
--- a/plinth/modules/openvpn/manifest.py
+++ b/plinth/modules/openvpn/manifest.py
@@ -5,14 +5,14 @@ Application manifest for OpenVPN.
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
 _package_id = 'de.blinkt.openvpn'
 _download_url = 'https://openvpn.net/community-downloads'
 
 backup = {'secrets': {'directories': ['/etc/openvpn/']}}
 
-clients = validate([{
+clients = [{
     'name':
         _('OpenVPN'),
     'platforms': [{
@@ -50,4 +50,4 @@ clients = validate([{
         'os': 'macos',
         'url': 'https://tunnelblick.net/downloads.html'
     }]
-}])
+}]
diff --git a/plinth/modules/performance/manifest.py b/plinth/modules/performance/manifest.py
index 22b616c51..3101ea0f3 100644
--- a/plinth/modules/performance/manifest.py
+++ b/plinth/modules/performance/manifest.py
@@ -5,12 +5,10 @@ FreedomBox app for System Monitoring (cockpit-pcp) in ‘System’.
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('Cockpit'),
     'platforms': [{
         'type': 'web',
         'url': '/_cockpit/system/graphs'
     }]
-}])
+}]
diff --git a/plinth/modules/quassel/manifest.py b/plinth/modules/quassel/manifest.py
index 8cab21ab4..fe3afcfb1 100644
--- a/plinth/modules/quassel/manifest.py
+++ b/plinth/modules/quassel/manifest.py
@@ -2,9 +2,9 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
-clients = validate([{
+clients = [{
     'name':
         _('Quassel'),
     'platforms': [{
@@ -42,7 +42,7 @@ clients = validate([{
         'store_name': 'google-play',
         'url': store_url('google-play', 'com.iskrembilen.quasseldroid'),
     }]
-}])
+}]
 
 backup = {
     'secrets': {
diff --git a/plinth/modules/radicale/manifest.py b/plinth/modules/radicale/manifest.py
index a341863ab..aded1f039 100644
--- a/plinth/modules/radicale/manifest.py
+++ b/plinth/modules/radicale/manifest.py
@@ -2,9 +2,9 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
-clients = validate([{
+clients = [{
     'name':
         _('DAVx5'),
     'usage':
@@ -76,7 +76,7 @@ clients = validate([{
         'type': 'web',
         'url': '/radicale/'
     }]
-}])
+}]
 
 backup = {
     'data': {
diff --git a/plinth/modules/roundcube/manifest.py b/plinth/modules/roundcube/manifest.py
index 30756b043..124b5ae69 100644
--- a/plinth/modules/roundcube/manifest.py
+++ b/plinth/modules/roundcube/manifest.py
@@ -2,14 +2,12 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('Roundcube'),
     'platforms': [{
         'type': 'web',
         'url': '/roundcube'
     }]
-}])
+}]
 
 backup = {}
diff --git a/plinth/modules/samba/manifest.py b/plinth/modules/samba/manifest.py
index 41869533c..6defc1d29 100644
--- a/plinth/modules/samba/manifest.py
+++ b/plinth/modules/samba/manifest.py
@@ -5,11 +5,11 @@ Application manifest for Samba.
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
 SHARES_CONF_BACKUP_FILE = '/var/lib/plinth/backups-data/samba-shares-dump.conf'
 
-clients = validate([{
+clients = [{
     'name':
         _('Android Samba Client'),
     'platforms': [{
@@ -74,7 +74,7 @@ clients = validate([{
         'os': 'gnu-linux',
         'url': 'https://kde.org/applications/system/org.kde.dolphin'
     }]
-}])
+}]
 
 backup = {
     'data': {
diff --git a/plinth/modules/searx/manifest.py b/plinth/modules/searx/manifest.py
index 8b260ce46..09f55904c 100644
--- a/plinth/modules/searx/manifest.py
+++ b/plinth/modules/searx/manifest.py
@@ -2,15 +2,13 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('Searx'),
     'platforms': [{
         'type': 'web',
         'url': '/searx/'
     }]
-}])
+}]
 
 PUBLIC_ACCESS_SETTING_FILE = '/etc/searx/allow_public_access'
 
diff --git a/plinth/modules/shaarli/manifest.py b/plinth/modules/shaarli/manifest.py
index d4258df40..93fe4d885 100644
--- a/plinth/modules/shaarli/manifest.py
+++ b/plinth/modules/shaarli/manifest.py
@@ -2,12 +2,10 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('Shaarli'),
     'platforms': [{
         'type': 'web',
         'url': '/shaarli'
     }]
-}])
+}]
diff --git a/plinth/modules/syncthing/manifest.py b/plinth/modules/syncthing/manifest.py
index 02b7d0293..565412612 100644
--- a/plinth/modules/syncthing/manifest.py
+++ b/plinth/modules/syncthing/manifest.py
@@ -2,12 +2,12 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
 _package_id = 'com.nutomic.syncthingandroid'
 _download_url = 'https://syncthing.net/'
 
-clients = validate([{
+clients = [{
     'name':
         _('Syncthing'),
     'platforms': [{
@@ -44,7 +44,7 @@ clients = validate([{
         'type': 'web',
         'url': '/syncthing'
     }]
-}])
+}]
 
 backup = {
     'secrets': {
diff --git a/plinth/modules/tor/manifest.py b/plinth/modules/tor/manifest.py
index 3a00a257d..3377bf261 100644
--- a/plinth/modules/tor/manifest.py
+++ b/plinth/modules/tor/manifest.py
@@ -2,13 +2,13 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
 _orbot_package_id = 'org.torproject.android'
 _tor_browser_download_url = \
     'https://www.torproject.org/download/download-easy.html'
 
-clients = validate([{
+clients = [{
     'name':
         _('Tor Browser'),
     'platforms': [{
@@ -38,7 +38,7 @@ clients = validate([{
         'store_name': 'f-droid',
         'url': store_url('f-droid', _orbot_package_id)
     }]
-}])
+}]
 
 backup = {
     'config': {
diff --git a/plinth/modules/transmission/manifest.py b/plinth/modules/transmission/manifest.py
index dd6dccad5..a9adbd834 100644
--- a/plinth/modules/transmission/manifest.py
+++ b/plinth/modules/transmission/manifest.py
@@ -2,15 +2,13 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import validate
-
-clients = validate([{
+clients = [{
     'name': _('Transmission'),
     'platforms': [{
         'type': 'web',
         'url': '/transmission'
     }]
-}])
+}]
 
 backup = {
     'data': {
diff --git a/plinth/modules/ttrss/manifest.py b/plinth/modules/ttrss/manifest.py
index 3c44b8e7e..7e0229277 100644
--- a/plinth/modules/ttrss/manifest.py
+++ b/plinth/modules/ttrss/manifest.py
@@ -2,9 +2,9 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
-clients = validate([{
+clients = [{
     'name':
         _('Tiny Tiny RSS (Fork)'),
     'platforms': [{
@@ -25,7 +25,7 @@ clients = validate([{
         'type': 'web',
         'url': '/tt-rss'
     }]
-}])
+}]
 
 backup = {
     'data': {
diff --git a/plinth/modules/wireguard/manifest.py b/plinth/modules/wireguard/manifest.py
index 61b2207c9..8ac7a8cee 100644
--- a/plinth/modules/wireguard/manifest.py
+++ b/plinth/modules/wireguard/manifest.py
@@ -5,11 +5,11 @@ Application manifest for WireGuard.
 
 from django.utils.translation import ugettext_lazy as _
 
-from plinth.clients import store_url, validate
+from plinth.clients import store_url
 
 _wireguard_package_id = 'com.wireguard.android'
 
-clients = validate([{
+clients = [{
     'name':
         _('WireGuard'),
     'platforms': [{
@@ -40,4 +40,4 @@ clients = validate([{
         'store_name': 'app-store',
         'url': 'https://apps.apple.com/us/app/wireguard/id1441195209'
     }]
-}])
+}]
diff --git a/plinth/tests/test_app.py b/plinth/tests/test_app.py
index 7b91d9f04..c2a05539d 100644
--- a/plinth/tests/test_app.py
+++ b/plinth/tests/test_app.py
@@ -10,6 +10,8 @@ import pytest
 
 from plinth.app import App, Component, FollowerComponent, Info, LeaderComponent
 
+# pylint: disable=protected-access
+
 
 class AppTest(App):
     """Sample App for testing."""
@@ -302,10 +304,17 @@ def test_info_initialization_without_args():
 
 def test_info_initialization_with_args():
     """Test initializing the Info component with arguments."""
+    clients = [{
+        'name': 'test',
+        'platforms': [{
+            'type': 'web',
+            'url': 'test-url'
+        }]
+    }]
     info = Info('test-app', 3, is_essential=True, depends=['test-app-2'],
                 name='Test App', icon='fa-test', icon_filename='test-icon',
                 short_description='For Test', description='Test description',
-                manual_page='Test', clients=['test'])
+                manual_page='Test', clients=clients)
     assert info.is_essential
     assert info.depends == ['test-app-2']
     assert info.name == 'Test App'
@@ -314,4 +323,19 @@ def test_info_initialization_with_args():
     assert info.short_description == 'For Test'
     assert info.description == 'Test description'
     assert info.manual_page == 'Test'
-    assert info.clients == ['test']
+    assert info.clients == clients
+
+
+def test_info_clients_validation():
+    """Test clients parameter validation during initialization."""
+    with pytest.raises(AssertionError):
+        Info('test-app', 3, clients='invalid')
+
+    clients = [{
+        'name': 'test',
+        'platforms': [{
+            'type': 'web',
+            'url': 'test-url'
+        }]
+    }]
+    Info('test-app', 3, clients=clients)