Dayon!

An easy-to-use, cross-platform remote desktop support solution for everyone It can be used as free alternative to various commercial remote desktop and remote assistance products.

Its key features are - no router or network configuration required on the assisted side - very low bandwidth usage - friendly, multilingual (de/en/es/fr/it/ru/tr/zh) user interface - assistant and assisted functionality in one packet - secure, end-to-end encrypted communication (TLS 1.3) - free and open source