Where can I find a stable server from which one could request a date?

Question

Unity

The bottom line: I want to charge the player some amount of money during his absence. I don’t want to focus on the time on the device: the game breaks too elementarily.
I have not worked with remote servers yet, so I can only imagine how to do it in the abstract.
First of all, as I believe, I need a stable server from which I could ask the current time, due to which I would calculate the time the player was absent from the game. Tell me what is better to use? Will a photon be suitable for this, or is it too bulky for such purposes?
I will be glad to any advice.
Thank you all in advance.

Answer 1

I found the answer for myself here .

Answer 2

NTP to invent for a new purpose worth it?