KDEConnect - KDE Community Wiki

This is the community page for KDE Connect. Feel free to edit it! It should contain useful and up to date resources for both users and developers.

What is KDE Connect?

KDE Connect is a project that enables all your devices to communicate with each other. Here's a few things KDE Connect can do:

Receive your phone notifications on your desktop computer and reply to messages
Control music playing on your desktop from your phone
Use your phone as a remote control for your desktop
Run predefined commands on your PC from connected devices. See the list of example commands for more details.
Check your phones battery level from the desktop
Ring your phone to help finding it
Share files and links between devices
Browse your phone from the desktop
Control the desktop's volume from the phone

To achieve this, KDE Connect:

implements a secure communication protocol over the network, and allows any developer to create plugins on top of it.
Has a component that you install on your desktop.
Has a KDE Connect client app you run on your phone.

This video from 2013 demonstrates some other cool features: https://www.youtube.com/watch?v=KkCFngNmsh0

More info at Albert Vaka's or Nico's blog.

Installation

You will most likely find the KDE Connect desktop component as a package in your distribution's repos. If not you can ask them to package it.

Despite a common misconception you can use KDE Connect on all desktop environments. Since most of the developers are using Plasma it may occur that a feature is broken or inaccessible on other desktop environments. In this case, please report it as a bug. There are multiple ways to enhance the KDE Connect experience on non-Plasma desktops. If you are a GNOME user you might prefer GSConnect, a GNOME shell extension. For desktops with AppIndicator support (Budgie, Cinnamon, LXDE, Pantheon, Unity) indicator-kdeconnect is available.

The app for Android can be found in both the Google Play Store and the free and open store F-Droid.

There was some development of a KDE Connect client app for iOS in 2014 (see source code) but due to our experience and various technical and organizational factors it's unlikely that we will have official iOS support anytime soon.

KDE Connect is also available on SailfishOS and we are working on bringing it to other Linux-based phones (Plasma Mobile, PostmarketOS etc.)

Browser Integration

Plasma Browser Integration makes KDE Connect even more powerful. It allows you to control content from e.g. Youtube or Netflix from your phone and send browser tabs to your phone. Despite the name it can also be used on non-Plasma desktops.

An alternative native extension for Chrome/Chromium (or compatible) and Firefox users, lets you "send pages and content from your browser to connected KDE Connect devices, via browser action or context menu." See its Github page for installation instructions.

Running KDE Connect over OpenVPN

There may be a variety of reasons for using KDE Connect with a VPN. Maybe you have left home and want to run a command or maybe you’re on a public wifi network where your devices aren’t allowed to communicate and you want to use remote control to give a presentation.

Set up Open VPN

If you have your own server with a public-facing IP address, you can set up OpenVPN yourself. OpenVPN is not the easiest piece of software to set up, but by following a setup tutorial such as this one, you should be able to manage: https://openvpn.net/howto.html

In order to allow UDP broadcast packets, which are what KDE Connect uses to automatically discover two devices, OpenVPN needs to be set up for bridging (TAP device). If you use a tun device, you can still manually connect by IP address.

If you want to rent a pre-configured OpenVPN service rather than set up your own it should work, but the same considerations about the server settings need to be taken into account.

Once the server is running, you can use the official OpenVPN client to connect the desktop to the server. There is no official OpenVPN client for Android, but I find that the OpenVPN for Android client works well: https://play.google.com/store/apps/details?id=de.blinkt.openvpn

Once both devices are connected, test that they are able to communicate over the VPN by trying to do a network ping between them.

Configure KDE Connect

If your OpenVPN instance is set up for bridging, KDE Connect should work just like on a local network

If you are using OpenVPN with a tun device, you will have to manually add your devices by IP. Then, once you connect to the VPN, KDE Connect should automatically detect your device and either connect or be ready for pairing!

Building KDE Connect (Desktop)

If you want to build KDE Connect yourself, you'll first need to grab the code from git.

git clone git://anongit.kde.org/kdeconnect-kde.git

KDE Connect uses cmake as a build system, which will tell you if you are missing any dependencies. On some distros you will need to install some development packages. On Ubuntu you can use sudo apt-get build-dep kdeconnect to install all build dependencies. On openSUSE you can use sudo zypper si -d kdeconnect-kde.

To configure use

cd kdeconnect-kde
mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr ..

To build use

make
sudo make install

If you are intending to develop KDE Connect or experience a crash and are asked to give a backtrace, build KDE Connect with debugging symbols:

cmake -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_BUILD_TYPE=Debug ..

If you install KDE Connect in a custom location you'll need to run kdeconnectd manually, since DBus doesn't know about it.

For instruction on how to integrate it in KDevelop check out this blog post

Building KDE Connect (Android)

You can find the code at git://anongit.kde.org/kdeconnect-android.git. It's easiest to use Android Studio to build the app and install it to your phone. Using the emulator is possible, but need an advanced networking setup (the emulator needs to be on the same subnet as the PC, or you won't be able to connect to your desktop.

Troubleshooting

I have two devices running KDE Connect on the same network, but they can't see each other

KDE Connect uses dynamic ports in the range 1714-1764 for UDP and TCP. So if you are behind a firewall, make sure to open this port range for both TCP and UDP. Otherwise, make sure your network is not blocking UDP broadcast packets.

ufw

If your firewall is ufw, you can open the necessary ports with:

sudo ufw allow 1714:1764/udp
sudo ufw allow 1714:1764/tcp
sudo ufw reload

firewalld

If your firewall is firewalld, you can open the necessary ports with:

sudo firewall-cmd --zone=public --permanent --add-port=1714-1764/tcp
sudo firewall-cmd --zone=public --permanent --add-port=1714-1764/udp
sudo systemctl restart firewalld.service

Fedora firewall

In Fedora there is a program to configure the firewall. Open Firewall Configuration (the program's filename is firewall-config), and in Zones > Services check the kde-connect service.

iptables

If your firewall is iptables, you can open the necessary ports with:

sudo iptables -A INPUT -i <yourinterface> -p udp --dport 1714:1764 -m state --state NEW,ESTABLISHED -j ACCEPT                                                                                                                          
sudo iptables -A INPUT -i <yourinterface> -p tcp --dport 1714:1764 -m state --state NEW,ESTABLISHED -j ACCEPT
 
sudo iptables -A OUTPUT -i <yourinterface> -p udp --sport 1714:1764 -m state --state NEW,ESTABLISHED -j ACCEPT                                                                                                                          
sudo iptables -A OUTPUT -i <yourinterface> -p tcp --sport 1714:1764 -m state --state NEW,ESTABLISHED -j ACCEPT

My KDE Connect crashes or restarts when trying to pair with another device

Sometimes, a corrupt config file may cause KDE Connect to crash when trying to pair with a device. In that case, deleting the config ~/.config/kdeconnect might help.

Can I run KDE Connect without a display server?

Yes, you can pass the command line argument `-platform offscreen` to the daemon (eg: `killall -9 kdeconnectd; /usr/lib/libexec/kdeconnectd -platform offscreen`)

My problem is not in this list :(

In case you find a bug and want to report it, you can do so in the KDE bug tracker.

Development

KDE Connect is a perfect project to start contributing to KDE. You'll need a basic understanding of programming concepts, the rest can be learned by doing. Experience with Android or Qt is beneficial, but not needed.

We have a group to discuss development. You can access it from Telegram, IRC (#kdeconnect) or matrix.org (#freenode_#kdeconnect:matrix.org). Feel free to ask any development related questions there, We also have a mailing list.

You can submit patches on our Phabricator. This wiki page has more details on how this process works. Should this be your first patch, it's good to know that it might take some time before your patch is reviewed (we all work on KDE Connect in our free time), and you'll probably have to make some changes a couple of times. That's not because you're new, that's what happens for all reviews (even for long-time contributors).

There are a couple of tasks marked as Junior Jobs on our workboard. Those have some extra information on how to approach them that help you get started.