A few years ago, while using the Line app, I noticed a feature called “People nearby” The feature would give you the exact distance from you to the other users. A few days ago, I installed Telegram, and I noticed that they have the same feature. An adversary can spoof their location for three points and use them to draw three triangulation circles. To verify this, I added one of the users and asked them if they live near the point, I was able to get that user’s exact home address.”]
Source: https://blog.ahmed.nyc/2021/01/if-you-use-this-feature-on-telegram.html