diff --git a/plinth/modules/diaspora/manifest.py b/plinth/modules/diaspora/manifest.py
index 0ec1578c8..1afd28ed2 100644
--- a/plinth/modules/diaspora/manifest.py
+++ b/plinth/modules/diaspora/manifest.py
@@ -31,11 +31,9 @@ clients = [{
     'platforms': [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
-        'os_version': '>4.2.0',
         'store_name': Store.F_DROID.value,
         'url': 'https://f-droid.org/repository/browse/?fdid=com'
                '.github.dfa.diaspora_android ',
-        'fully_qualified_name': 'com.github.dfa.diaspora_android'
     }]
 }, {
     'name':
diff --git a/plinth/modules/ejabberd/manifest.py b/plinth/modules/ejabberd/manifest.py
index c35fa1767..b80eca90a 100644
--- a/plinth/modules/ejabberd/manifest.py
+++ b/plinth/modules/ejabberd/manifest.py
@@ -19,17 +19,20 @@ from django.utils.translation import ugettext_lazy as _
 
 from plinth.modules.jsxc import manifest as jsxc_manifest
 from plinth.templatetags.plinth_extras import Desktop_OS, Mobile_OS, Store
+from plinth.utils import play_store_url
 
-clients = [{
+yaxim_package_id = 'org.yaxim.androidclient'
+bruno_package_id = 'org.yaxim.bruno'
+conversations_package_id = 'eu.siacs.conversations'
+
+_clients = [{
     'name':
         _('yaxim'),
     'platforms': [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'fully_qualified_name': 'org.yaxim.androidclient',
-        'url': 'https://play.google.com/store/apps/details?id=org'
-               '.yaxim.androidclient '
+        'url': play_store_url(yaxim_package_id),
     }]
 }, {
     'name':
@@ -41,9 +44,7 @@ clients = [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'fully_qualified_name': 'org.yaxim.bruno',
-        'url': 'https://play.google.com/store/apps/details?id'
-               '=org.yaxim.bruno '
+        'url': play_store_url(bruno_package_id)
     }]
 }, {
     'name':
@@ -70,49 +71,30 @@ clients = [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'url': 'https://play.google.com/store/apps/details?id'
-               '=eu.siacs.conversations ',
-        'fully_qualified_name': 'eu.siacs.conversations'
+        'url': play_store_url(conversations_package_id)
     }]
 }, {
     'name':
         _('Dino'),
     'platforms': [{
         'type': 'download',
-        'os': 'Debian',
-        'url': 'https://download.opensuse.org/repositories/network'
-               ':/messaging:/xmpp:/dino/Debian_9.0/amd64/dino_0.0'
-               '~git178.9d8e1e8_amd64.deb',
+        'os': Desktop_OS.GNU_LINUX,
+        'url': 'https://github.com/dino/dino/wiki/Distribution-Packages',
     }]
 }, {
     'name':
         _('Gajim'),
     'platforms': [{
-        'type': 'apt',
+        'type': 'package',
         'os': 'Debian',
         'package_name': 'gajim'
     }, {
         'type': 'download',
         'os': Desktop_OS.WINDOWS.value,
-        'url': 'https://gajim.org/downloads/0.16/gajim-0.16.8-2.exe'
+        'url': 'https://gajim.org/downloads.php'
     }]
-}, {
-    'name':
-        _('OneTeam'),
-    'platforms': [{
-        'type': 'download',
-        'os': Desktop_OS.WINDOWS.value,
-        'url': 'https://download.process-one.net/oneteam/release'
-               '-installers/OneTeam.msi'
-    }, {
-        'type': 'download',
-        'os': Desktop_OS.MAC_OS.value,
-        'url': 'https://download.process-one.net/oneteam/release'
-               '-installers/OneTeam.dmg '
-    }, {
-        'type': 'download',
-        'os': 'Linux',
-        'url': 'https://download.process-one.net/oneteam/release'
-               '-installers/oneteam.tar.bz2 '
-    }]
-}].append(jsxc_manifest.clients)
+}]
+
+_clients.extend(jsxc_manifest.clients)
+
+clients = _clients
diff --git a/plinth/modules/infinoted/manifest.py b/plinth/modules/infinoted/manifest.py
index 72f6db676..46b1d3502 100644
--- a/plinth/modules/infinoted/manifest.py
+++ b/plinth/modules/infinoted/manifest.py
@@ -36,7 +36,7 @@ clients = [{
         'os': Desktop_OS.WINDOWS.value,
         'url': 'http://releases.0x539.de/gobby/gobby-stable.exe'
     }, {
-        'type': 'apt',
+        'type': 'package',
         'os': 'Debian',
         'package_name': 'gobby'
     }]
diff --git a/plinth/modules/jsxc/manifest.py b/plinth/modules/jsxc/manifest.py
index 313db43d0..4c83196e8 100644
--- a/plinth/modules/jsxc/manifest.py
+++ b/plinth/modules/jsxc/manifest.py
@@ -17,15 +17,15 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-clients = [
-    {
-        'name': _('JSXC'),
-        'platforms': [
-            {
-                'type': 'apt',
-                'os': 'Debian',
-                'package_name': 'libjs-jsxc'
-            }
-        ]
-    }
-]
+clients = [{
+    'name':
+        _('JSXC'),
+    'platforms': [{
+        'type': 'package',
+        'os': 'Debian',
+        'package_name': 'libjs-jsxc'
+    }, {
+        'type': 'web',
+        'url': '/jsxc'
+    }]
+}]
diff --git a/plinth/modules/matrixsynapse/manifest.py b/plinth/modules/matrixsynapse/manifest.py
index 0a981ce0e..9023f192e 100644
--- a/plinth/modules/matrixsynapse/manifest.py
+++ b/plinth/modules/matrixsynapse/manifest.py
@@ -18,6 +18,10 @@
 from django.utils.translation import ugettext_lazy as _
 
 from plinth.templatetags.plinth_extras import Desktop_OS, Mobile_OS, Store
+from plinth.utils import f_droid_url, play_store_url
+
+android_package_id = 'im.vector.alpha'
+riot_desktop_download_url = 'https://riot.im/desktop.html'
 
 clients = [{
     'name':
@@ -27,17 +31,13 @@ clients = [{
             'type': 'store',
             'os': Mobile_OS.ANDROID.value,
             'store_name': Store.GOOGLE_PLAY.value,
-            'fully_qualified_name': 'im.vector.alpha',
-            'url': 'https://play.google.com/store/apps/details?id=im'
-                   '.vector.alpha '
+            'url': play_store_url(android_package_id)
         },
         {
             'type': 'store',
             'os': Mobile_OS.ANDROID.value,
-            'os_version': '>=6.0',
             'store_name': Store.F_DROID.value,
-            'fully_qualified_name': 'im.vector.alpha',
-            'url': 'https://f-droid.org/packages/im.vector.alpha/'
+            'url': f_droid_url(android_package_id)
         },
         {
             'type': 'web',
@@ -46,18 +46,17 @@ clients = [{
         {
             'type': 'download',
             'os': Desktop_OS.GNU_LINUX.value,
-            'url': 'https://riot.im/desktop.html'
+            'url': riot_desktop_download_url,
         },
         {
             'type': 'download',
             'os': Desktop_OS.MAC_OS.value,
-            'url': 'https://riot.im/desktop.html'
+            'url': riot_desktop_download_url,
         },
         {
             'type': 'download',
             'os': Desktop_OS.WINDOWS.value,
-            'os_version': '>=7',
-            'url': 'https://riot.im/desktop.html'
+            'url': riot_desktop_download_url,
         },
     ]
 }]
diff --git a/plinth/modules/minetest/manifest.py b/plinth/modules/minetest/manifest.py
index db556ba63..90332ff7d 100644
--- a/plinth/modules/minetest/manifest.py
+++ b/plinth/modules/minetest/manifest.py
@@ -25,22 +25,18 @@ clients = [{
     'platforms': [{
         'type': 'download',
         'os': Desktop_OS.WINDOWS.value,
-        'arch': 'amd64',
-        'os_version': 'XP, Vista, >=7',
         'url': 'https://github.com/minetest/minetest/releases'
                '/download/0.4.16/minetest-0.4.16-win64.zip '
     }, {
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'fully_qualified_name': 'net.minetest.minetest',
         'url': 'https://play.google.com/store/apps/details?id=net'
                '.minetest.minetest '
     }, {
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.F_DROID.value,
-        'fully_qualified_name': 'net.minetest.minetest',
         'url': 'https://f-droid.org/packages/net.minetest.minetest/ '
     }, {
         'type': 'package',
diff --git a/plinth/modules/mumble/manifest.py b/plinth/modules/mumble/manifest.py
index f9aaf7b30..c3b950bdb 100644
--- a/plinth/modules/mumble/manifest.py
+++ b/plinth/modules/mumble/manifest.py
@@ -18,6 +18,9 @@
 from django.utils.translation import ugettext_lazy as _
 
 from plinth.templatetags.plinth_extras import Desktop_OS, Mobile_OS, Store
+from plinth.utils import f_droid_url, play_store_url
+
+plumble_package_id = 'com.morlunk.mumbleclient.free'
 
 clients = [{
     'name':
@@ -25,14 +28,11 @@ clients = [{
     'platforms': [{
         'type': 'download',
         'os': Desktop_OS.WINDOWS.value,
-        'arch': 'amd64',
-        'url': 'https://dl.mumble.info/mumble-1.3.0~2569~gd196a4b'
-               '~snapshot.winx64.msi '
+        'url': 'https://wiki.mumble.info/wiki/Main_Page'
     }, {
         'type': 'download',
         'os': Desktop_OS.MAC_OS.value,
-        'url': 'https://github.com/mumble-voip/mumble/releases'
-               '/download/1.2.19/Mumble-1.2.19.dmg '
+        'url': 'https://wiki.mumble.info/wiki/Main_Page'
     }, {
         'type': 'package',
         'format': 'deb',
@@ -40,7 +40,6 @@ clients = [{
     }, {
         'type': 'store',
         'os': Mobile_OS.IOS.value,
-        'os_version': '>=8.0',
         'store_name': Store.APP_STORE.value,
         'url': 'https://itunes.apple.com/us/app/mumble/id443472808'
     }]
@@ -51,16 +50,12 @@ clients = [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'url': 'https://play.google.com/store/apps/details?id=com'
-               '.morlunk.mumbleclient.free ',
-        'fully_qualified_name': 'com.morlunk.mumbleclient'
+        'url': play_store_url(plumble_package_id)
     }, {
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.F_DROID.value,
-        'url': 'https://play.google.com/store/apps/details?id=com'
-               '.morlunk.mumbleclient.free ',
-        'fully_qualified_name': 'com.morlunk.mumbleclient'
+        'url': f_droid_url(plumble_package_id)
     }]
 }, {
     'name':
@@ -68,7 +63,6 @@ clients = [{
     'platforms': [{
         'type': 'store',
         'os': Mobile_OS.IOS.value,
-        'os_version': '>=7.0',
         'store_name': Store.APP_STORE.value,
         'url': 'https://itunes.apple.com/dk/app/mumblefy/id858752232'
     }]
diff --git a/plinth/modules/quassel/manifest.py b/plinth/modules/quassel/manifest.py
index f886cd440..f763f28ff 100644
--- a/plinth/modules/quassel/manifest.py
+++ b/plinth/modules/quassel/manifest.py
@@ -18,6 +18,10 @@
 from django.utils.translation import ugettext_lazy as _
 
 from plinth.templatetags.plinth_extras import Desktop_OS, Mobile_OS, Store
+from plinth.utils import play_store_url
+
+quasseldroid_package_id = 'com.iskrembilen.quasseldroid',
+quassel_download_url = 'http://quassel-irc.org/downloads'
 
 clients = [{
     'name':
@@ -25,12 +29,11 @@ clients = [{
     'platforms': [{
         'type': 'download',
         'os': Desktop_OS.MAC_OS.value,
-        'url': 'http://quassel-irc.org/pub/QuasselClient_MacOSX'
-               '-x86_64_0.12.4.dmg'
+        'url': quassel_download_url,
     }, {
-        'type': 'apt',
+        'type': 'package',
         'os': 'Debian',
-        'package_name': 'quassel-client'
+        'package_name': 'quassel-client',
     }]
 }, {
     'name':
@@ -39,8 +42,6 @@ clients = [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'url': 'https://play.google.com/store/apps/details?id=com'
-               '.iskrembilen.quasseldroid',
-        'fully_qualified_name': 'com.iskrembilen.quasseldroid'
+        'url': play_store_url(quasseldroid_package_id),
     }]
 }]
diff --git a/plinth/modules/radicale/manifest.py b/plinth/modules/radicale/manifest.py
index 3addbf01b..ec44426f9 100644
--- a/plinth/modules/radicale/manifest.py
+++ b/plinth/modules/radicale/manifest.py
@@ -18,6 +18,9 @@
 from django.utils.translation import ugettext_lazy as _
 
 from plinth.templatetags.plinth_extras import Mobile_OS, Store
+from plinth.utils import play_store_url
+
+davdroid_package_id = 'at.bitfire.davdroid'
 
 clients = [{
     'name':
@@ -31,15 +34,13 @@ clients = [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'url': 'https://play.google.com/store/apps/details?id=at'
-               '.bitfire.davdroid',
-        'fully_qualified_name': 'at.bitfire.davdroid'
+        'url': play_store_url(davdroid_package_id),
     }]
 }, {
     'name':
         _('GNOME Calendar'),
     'platforms': [{
-        'type': 'apt',
+        'type': 'package',
         'os': 'Debian',
         'package-name': 'gnome-calendar'
     }]
@@ -57,7 +58,7 @@ clients = [{
           'Clicking on the search button will list the existing '
           'calendars and address books.'),
     'platforms': [{
-        'type': 'apt',
+        'type': 'package',
         'os': 'Debian',
         'package-name': 'gnome-calendar'
     }]
diff --git a/plinth/modules/repro/manifest.py b/plinth/modules/repro/manifest.py
index b3b036368..9e3ed6160 100644
--- a/plinth/modules/repro/manifest.py
+++ b/plinth/modules/repro/manifest.py
@@ -18,6 +18,12 @@
 from django.utils.translation import ugettext_lazy as _
 
 from plinth.templatetags.plinth_extras import Desktop_OS, Mobile_OS, Store
+from plinth.utils import play_store_url
+
+jitsi_package_id = 'org.jitsi.meet'
+csipsimple_package_id = 'com.csipsimple'
+
+jitsi_download_url = 'https://download.jitsi.org/jitsi/'
 
 clients = [{
     'name':
@@ -35,9 +41,7 @@ clients = [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'fully_qualified_name': 'org.jitsi.meet',
-        'url': 'https://play.google.com/store/apps/details?id=org'
-               '.jitsi.meet '
+        'url': play_store_url(jitsi_package_id)
     }, {
         'type': 'store',
         'os': Mobile_OS.IOS.value,
@@ -46,7 +50,7 @@ clients = [{
     }, {
         'type': 'download',
         'os': Desktop_OS.GNU_LINUX.value,
-        'url': 'https://download.jitsi.org/jitsi/debian/'
+        'url': jitsi_download_url
     }, {
         'type': 'package',
         'format': 'deb',
@@ -54,13 +58,11 @@ clients = [{
     }, {
         'type': 'download',
         'os': Desktop_OS.MAC_OS.value,
-        'url': 'https://download.jitsi.org/jitsi/macosx/jitsi-latest'
-               '.dmg '
+        'url': jitsi_download_url
     }, {
         'type': 'download',
         'os': Desktop_OS.WINDOWS.value,
-        'url': 'https://download.jitsi.org/jitsi/windows/jitsi-latest'
-               '-x86.exe '
+        'url': jitsi_download_url
     }]
 }, {
     'name':
@@ -69,8 +71,6 @@ clients = [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'fully_qualified_name': 'com.csipsimple',
-        'url': 'https://play.google.com/store/apps/details?id=com'
-               '.csipsimple '
+        'url': play_store_url(csipsimple_package_id)
     }]
 }]
diff --git a/plinth/modules/syncthing/manifest.py b/plinth/modules/syncthing/manifest.py
index 3ec6de5fc..230417da0 100644
--- a/plinth/modules/syncthing/manifest.py
+++ b/plinth/modules/syncthing/manifest.py
@@ -18,13 +18,10 @@
 from django.utils.translation import ugettext_lazy as _
 
 from plinth.templatetags.plinth_extras import Desktop_OS, Mobile_OS, Store
+from plinth.utils import f_droid_url, play_store_url
 
-metadata = {
-    'syncthing': {
-        'version': '0.14.39',
-        'android-package-id': 'com.nutomic.syncthingandroid',
-    },
-}
+syncthing_package_id = 'com.nutomic.syncthingandroid'
+syncthing_download_url = 'https://syncthing.net/'
 
 clients = [{
     'name':
@@ -40,48 +37,25 @@ clients = [{
     }, {
         'type': 'download',
         'os': Desktop_OS.GNU_LINUX.value,
-        'arch': 'amd64',
-        'url': 'https://github.com/syncthing/syncthing/releases/'
-               'download/v{0}/syncthing-linux-amd64-v{0}.tar.gz'
-               .format(metadata['syncthing']['version']),
+        'url': syncthing_download_url,
     }, {
         'type': 'download',
         'os': Desktop_OS.MAC_OS.value,
-        'arch': 'amd64',
-        'url': 'https://github.com/syncthing/syncthing/releases/'
-               'download/v{0}/syncthing-macosx-amd64-v{0}.tar.gz'
-               .format(metadata['syncthing']['version']),
+        'url': syncthing_download_url,
     }, {
         'type': 'download',
         'os': Desktop_OS.WINDOWS.value,
-        'arch': 'amd64',
-        'url': 'https://github.com/syncthing/syncthing/releases/'
-               'download/v{0}/syncthing-windows-amd64-v{0}.zip'
-               .format(metadata['syncthing']['version']),
+        'url': syncthing_download_url,
     }, {
-        'type':
-            'store',
-        'os':
-            Mobile_OS.ANDROID.value,
-        'store_name':
-            Store.GOOGLE_PLAY.value,
-        'fully_qualified_name':
-            metadata['syncthing']['android-package-id'],
-        'url':
-            'https://play.google.com/store/apps/details?id={}'
-            .format(metadata['syncthing']['android-package-id'])
+        'type': 'store',
+        'os': Mobile_OS.ANDROID.value,
+        'store_name': Store.GOOGLE_PLAY.value,
+        'url': play_store_url(syncthing_package_id)
     }, {
-        'type':
-            'store',
-        'os':
-            Mobile_OS.ANDROID.value,
-        'store_name':
-            Store.F_DROID.value,
-        'fully_qualified_name':
-            metadata['syncthing']['android-package-id'],
-        'url':
-            'https://f-droid.org/packages/{}'
-            .format(metadata['syncthing']['android-package-id'])
+        'type': 'store',
+        'os': Mobile_OS.ANDROID.value,
+        'store_name': Store.F_DROID.value,
+        'url': f_droid_url(syncthing_package_id)
     }, {
         'type': 'web',
         'url': '/syncthing'
diff --git a/plinth/modules/tor/manifest.py b/plinth/modules/tor/manifest.py
index 2216dc72c..fff134bf2 100644
--- a/plinth/modules/tor/manifest.py
+++ b/plinth/modules/tor/manifest.py
@@ -18,8 +18,10 @@
 from django.utils.translation import ugettext_lazy as _
 
 from plinth.templatetags.plinth_extras import Desktop_OS, Mobile_OS, Store
+from plinth.utils import f_droid_url, play_store_url
 
-version = '7.0.6'
+orbot_package_id = 'org.torproject.android'
+tor_browser_download_url = 'https://www.torproject.org/download/download-easy.html'
 
 clients = [{
     'name':
@@ -27,20 +29,15 @@ clients = [{
     'platforms': [{
         'type': 'download',
         'os': Desktop_OS.WINDOWS.value,
-        'os_version': 'Windows XP, Vista, >=7',
-        'url': 'https://www.torproject.org/dist/torbrowser/{v}'
-               '/torbrowser-install-{v}_en-US.exe '.format(v=version)
+        'url': tor_browser_download_url,
     }, {
         'type': 'download',
         'os': Desktop_OS.GNU_LINUX.value,
-        'url': 'https://www.torproject.org/dist/torbrowser/{v}/tor'
-               '-browser-linux64-{v} _en-US.tar.xz'.format(v=version)
+        'url': tor_browser_download_url,
     }, {
         'type': 'download',
         'os': Desktop_OS.MAC_OS.value,
-        'arch': 'amd64',
-        'url': 'https://www.torproject.org/dist/torbrowser/{v}'
-               '/TorBrowser-{v}-osx64_en-US.dmg'.format(v=version)
+        'url': tor_browser_download_url,
     }]
 }, {
     'name':
@@ -49,15 +46,11 @@ clients = [{
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.GOOGLE_PLAY.value,
-        'url': 'https://play.google.com/store/apps/details?id=org'
-               '.torproject.android',
-        'fully_qualified_name': 'org.torproject.android'
+        'url': play_store_url(orbot_package_id)
     }, {
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.F_DROID.value,
-        'url': 'https://play.google.com/store/apps/details?id=org'
-               '.torproject.android',
-        'fully_qualified_name': 'org.torproject.android'
+        'url': f_droid_url(orbot_package_id)
     }]
 }]
diff --git a/plinth/modules/ttrss/manifest.py b/plinth/modules/ttrss/manifest.py
index 92cbbab5b..d4ee2cb6b 100644
--- a/plinth/modules/ttrss/manifest.py
+++ b/plinth/modules/ttrss/manifest.py
@@ -28,13 +28,11 @@ clients = [{
         'store_name': Store.GOOGLE_PLAY.value,
         'url': 'https://play.google.com/store/apps/details?id=org'
                '.ttrssreader',
-        'fully_qualified_name': 'org.ttrssreader'
     }, {
         'type': 'store',
         'os': Mobile_OS.ANDROID.value,
         'store_name': Store.F_DROID.value,
         'url': 'https://f-droid.org/packages/org.ttrssreader/',
-        'fully_qualified_name': 'org.ttrssreader'
     }, {
         'type': 'web',
         'url': '/tt-rss'
diff --git a/plinth/templatetags/plinth_extras.py b/plinth/templatetags/plinth_extras.py
index 0b13671fb..efe4541cf 100644
--- a/plinth/templatetags/plinth_extras.py
+++ b/plinth/templatetags/plinth_extras.py
@@ -40,7 +40,7 @@ class Store(Enum):
     GOOGLE_PLAY = 'google-play'
 
 
-def string_values(enum):
+def enum_values(enum):
     return [x.value for x in list(enum)]
 
 
@@ -94,14 +94,14 @@ def __check(clients, cond):
 def has_desktop_clients(clients):
     """Filter to find out whether an application has desktop clients"""
     return __check(clients,
-                   lambda x: x.get('os', '') in string_values(Desktop_OS))
+                   lambda x: x.get('os', '') in enum_values(Desktop_OS))
 
 
 @register.filter(name='has_mobile_clients')
 def has_mobile_clients(clients):
     """Filter to find out whether an application has mobile clients"""
     return __check(clients,
-                   lambda x: x.get('os', '') in string_values(Mobile_OS))
+                   lambda x: x.get('os', '') in enum_values(Mobile_OS))
 
 
 @register.filter(name='has_web_clients')
@@ -112,12 +112,10 @@ def has_web_clients(clients):
 
 @register.filter(name='of_type')
 def of_type(clients, typ):
-    """Filter clients of a particular type"""
-    if typ == 'mobile':
-        return list(filter(has_mobile_clients, clients))
-    elif typ == 'desktop':
-        return list(filter(has_desktop_clients, clients))
-    elif typ == 'web':
-        return list(filter(has_web_clients, clients))
-    else:
-        return clients
+    """Filter and get clients of a particular type"""
+    filters = {
+        'mobile': has_mobile_clients,
+        'desktop': has_desktop_clients,
+        'web': has_web_clients
+    }
+    return list(filter(filters.get(typ, lambda x: x), clients))
diff --git a/plinth/utils.py b/plinth/utils.py
index e0a6856db..20ccfe6ac 100644
--- a/plinth/utils.py
+++ b/plinth/utils.py
@@ -14,15 +14,16 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
-
 """
 Miscellaneous utility methods.
 """
 
 import importlib
 import os
-import ruamel.yaml
+
 from django.utils.functional import lazy
+
+import ruamel.yaml
 from plinth.modules import names
 
 
@@ -83,12 +84,14 @@ def get_domain_names():
 
 class YAMLFile(object):
     """A context management class for updating YAML files"""
+
     def __init__(self, yaml_file, post_exit=None):
         """Return a context object for the YAML file.
 
         Parameters:
         yaml_file - the YAML file to update.
-        post_exit - a function that will be called after updating the YAML file.
+        post_exit - a function that will be called after
+        updating the YAML file.
         """
         self.yaml_file = yaml_file
         self.post_exit = post_exit
@@ -112,3 +115,12 @@ class YAMLFile(object):
 
     def is_file_empty(self):
         return os.stat(self.yaml_file).st_size == 0
+
+
+def play_store_url(package_id):
+    return 'https://play.google.com/store/apps/details?id={}'.format(
+        package_id)
+
+
+def f_droid_url(package_id):
+    return 'https://f-droid.org/packages/{}'.format(package_id)