The notifications are sent to any client that has an open two-way connection (TCP socket or WebSocket) to the XBMC client sending the notifications.
Always read the online manual(wiki), FAQ(wiki) and search the forum before posting.
Do not e-mail Team Kodi members directly asking for support. Read/follow the forum rules(wiki).
Please read the pages on troubleshooting(wiki) and bug reporting(wiki) before reporting issues.