How does 8 ball pool determine the country?
Solution 1:
Without some serious investigation, I can't guarantee this is accurate for this specific app, however:
The standard way for apps to detect a users country would be to use the phones own inbuilt location services. This is a service provided by the phones operating system that allows apps to access various information about the phones physical location. They can vary depending on what device you use, but all major phone providers have something along these lines.
They generally use whatever methods they have access to at the time, to determine your location, for instance GPS will generally be used first, but if this is not available it may fall back to cellular networks or WiFi addresses.
Apple describe this here:
With your permission, Location Services allows apps and websites (including Maps, Camera, Weather, and other apps) to use information from cellular, Wi-Fi, Global Positioning System (GPS) networks, and Bluetooth to determine your approximate location.