12:03 PM
@KaleemRehman yes occasionally having each user send their location to a central DB seems sensible. How often this should happen depends on your use case and on the scale of your map. You might want to regularly delete outdated locations, some DBs like Redis can expire old entries automatically.
Of course, please consider the privacy implications of showing location data to other users. Many apps hide the real location by selecting a made-up location some distance away, and then draw a circle around the made-up location that is large enough to also contain the real location. A similar technique is to divide the map into a grid, and only show on which grid cell the user is.
@KaleemRehman please disregard Duga, she is a bot who collects some comments from StackOverflow.
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