How to update the application without google play?

Question

Unity

Hello, such a question, I have no idea how to implement it, although there are ideas.
the essence of the question: how to update the application without google play, that is, I make a change in the game on the unit, and those who have my application see these changes, despite the fact that I just transferred the application as an apk file.
Can this be implemented somehow?
If so, please describe in detail, with links, or a video from YouTube, I will be grateful, because I am just starting to learn units and c#.

Answer 1

Separate server with application versions. The client must have some background service that periodically asks the server for a new update.
After the consent of the client, download and install.
Telegram does this if you download the apk through their website, and not through the market