KDE Connect links your phone and your computer. It synchronises notifications, shares files, links and the clipboard, lets you reply to text messages from the computer, and turns the phone into a remote control for media players, a touchpad or a presentation clicker. You can also ring your phone and see its battery level. Apps exist for Linux, Windows, macOS, Android and iOS. The devices talk to each other wirelessly using TLS encryption; it runs as a desktop and mobile app rather than as a vendor-operated service.
KDE Connect is developed by the KDE community. The association KDE e.V. has its registered seat in Berlin, Germany. The software is free software under the GPL v2 and v3, so you can inspect and build the source code yourself. New versions appear regularly. Improvements to its discovery and transport protocol were co-funded through NLnet and the EU's NGI Zero programme between 2022 and 2024. According to the README, the devices discover each other on the network and exchange data directly; no server operated by the developers is mentioned.