Gotify
Gotify is a simple, self-hosted server for sending and receiving messages. It is designed with a user-friendly interface and a straightforward API, making it easy to use across different platforms. The core of Gotify is the server, which features a WebUI and functionality for sending messages via a REST-API, subscribing/receiving messages via a web socket connection, and managing users, clients, and applications. Gotify also includes an Android client for subscribing to the message stream of the server, creating push notifications for newly received messages. Additionally, there is a command line client for pushing messages to the server. All these features make Gotify a versatile tool for managing and exchanging messages while maintaining control over your data.