diff --git a/sites/en/services/connectivitycheck.md b/sites/en/services/connectivitycheck.md
index b8ecb4a..ed73209 100644
--- a/sites/en/services/connectivitycheck.md
+++ b/sites/en/services/connectivitycheck.md
@@ -5,4 +5,56 @@ title: Captive Portal Check
 ---
 # Captive Portal Check
 
-The description for the Captive Portal Check is coming soon.
+A captive portal is a login page in public WLAN networks to restrict Internet access to the approval of certain terms of use. When you see a login page on a public network, your device uses a captive portal check. This allows the device to find out whether you have direct Internet access or not. In Android, for example, your device sends a request to a Google server.
+
+Since mid 2019 I provide a free Captive Portal Check: [https://connectivitycheck.sp-codes.de/generate204](https://connectivitycheck.sp-codes.de/generate204) You are welcome to use it if you like.
+
+## Setup in Android
+
+To change the Captive Portal Check in Android, you need a terminal app or a connection via ADB to a computer.
+
+To use `http` you can run the following commands with the respective method:
+
+```
+# settings put global captive_portal_use_https 0
+# settings put global captive_portal_http_url "http://connectivitycheck.sp-codes.de/generate204"
+```
+
+To use `https` you can use the following two commands:
+
+```
+# settings put global captive_portal_use_https 1
+# settings put global captive_portal_https_url "https://connectivitycheck.sp-codes.de/generate204"
+```
+
+Maybe you have to reboot your phone after updating the settings.
+
+If you are using AFWall+ you need to give access to _[1000] Android-System_ and in some cases _[10040] CaptivePortalLogin_ to make it work.
+
+## Setup in Ubuntu
+
+In Ubuntu, the file `/etc/NetworkManager/NetworkManager.conf` must be changed. Add or change the following lines:
+
+```
+[connectivity]
+uri=https://connectivitycheck.sp-codes.de/generate204
+```
+
+Restart the network-manager:
+
+```
+sudo service network-manager restart
+```
+
+## Setup in Firefox
+
+Type [about:config](about:config) in the Firefox address bar and search for `captivedetect.canonicalURL` and `network.connectivity-service`. Set the URL values to `https://connectivitycheck.sp-codes.de/generate204`, the domain values to `connectivitycheck.sp-codes.de`. That's it.
+
+## More useful links
+
+* [Captive Portal Wikipedia](https://en.wikipedia.org/wiki/Captive_portal)
+* [Source code](https://git.sp-codes.de/samuel-p/connectivity-check)
+* [Docker Image](https://hub.docker.com/r/samuelph/connectivity-check)
+* [Setup on Android](https://android.stackexchange.com/a/186995/288049)
+* [Setup on Ubuntu](https://askubuntu.com/q/1167177/920103)
+* [Captive Portal Kuketz Blog](https://www.kuketz-blog.de/android-captive-portal-check-204-http-antwort-von-captiveportal-kuketz-de/)
diff --git a/sites/en/services/invidious.md b/sites/en/services/invidious.md
index 3e2e229..00d27f7 100644
--- a/sites/en/services/invidious.md
+++ b/sites/en/services/invidious.md
@@ -5,4 +5,13 @@ title: Invidious
 ---
 # Invidious
 
-The description for Invidious is coming soon.
+Invidious is an alternative YouTube-Frontend. It establishes only the most necessary connections to YouTube and many of them are even made by the server itself. So Invidious increases the privacy of the users.
+
+__Since December 2019 I run a public Invidious instance.__ Feel free to watch some videos there.
+
+__Watch your first video on [invidious.sp-codes.de](https://invidious.sp-codes.de).__
+
+## More useful links
+
+* [List of other public servers](https://github.com/omarroth/invidious/wiki/Invidious-Instances)
+* [Source code of Invidious](https://github.com/omarroth/invidious)