RustDesk

Description: Open source virtual / remote desktop infrastructure for everyone!
Interface: GUI, CLI
License: open-source
Homepage
Platforms: Windows 32-bit, 64-bit, Linux, MacOS, Android, iOS
Commentary: Docs are here. A web client exists (in beta).
Usage Example: 

Screenshot:

Additional Details: 

Pre-configure the client - change the EXE to the following (replacing the server host/ip and key with your own):
rustdesk-host=yourserver.domain.com,key=EwUv6qPuJwTR+KJXrM0FRfd4ke2bfe3o5oA+ZQkRwRQ=.exe

There is a --tray switch in the RustDesk.exe client (ver 1.1.9) but it's not clear if it's fully supported in service mode. Adding it to the server command line does not appear to run the client in the tray.

There is currently no "address book" feature in the self-hosted open-source edition. There is no way  (in the app) to keep track of remote devices beyond what you've added to the client interface.

When the client spawns a connection, it uses this command line:
"rustdesk-host=yourserver.domain.com,key=EwUv6qPuJwTR+KJXrM0FRfd4ke2bfe3o5oA+ZQkRwRQ=.exe" --connect 665258521

Devices that do connect to the server appear to be stored in the server's sqlite database (db_v2.sqlite3) at c:\Users\%username%\AppData\Roaming\RustDesk\config\ in the 'peer' table - there doesn't seem to be anything to indicate active or recent connections: