Hello,
We have worked with geolocation feature earlier however we have not worked geolocation feature with a chat application. We have worked with both the features separately so we have an experience here and can do what you are looking for. Basically, you need the feature where users can locate nearby person and chat with them if they are also using that application.
We can share our experience in apps for a reference. If you have any questions, please contact us. We look forward to your response.
Regards,
OKTeam