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Show HN: Pintalk – Public, location-based chat rooms on a map

Hi HN,

I've been thinking about Paul Graham's idea of Twitter as a communication protocol https://www.paulgraham.com/twitter.html and wanted to experiment with a different kind: location-based chat.

I built Pintalk: https://pintalk.onrender.com

It's a simple web app that lets anyone start or join public text conversations tied to specific latitude/longitude coordinates on a map.

How it works:

Visit the site – the map tries to center near you using browser geolocation or falls back to IP lookup.

Click anywhere on the map to open a chat panel for that location.

Type your first message and hit send – this creates a persistent pin and conversation room at that spot.

Click an existing pin to view the conversation and join in.

No login or registration required. You get assigned a temporary username like User_1234. Messages and pins currently stay indefinitely.

The goal was minimal time-to-value – just click and chat. It's an experiment in discovering real-time, hyperlocal public discussions. What happens when conversations are anchored to places?

Tech: Node.js/Express, WebSockets, MongoDB/Mongoose, and Leaflet.js on the frontend. Deployed on Render.

It's basic right now but functional. I'd love to get your feedback, bug reports, or thoughts on the concept.

Try it out: https://pintalk.onrender.com

Thanks!

( 4 comments | 3 points | on HN )
Re:Show HN: Pintalk – Public, location-based chat rooms on a... by marcrall on Monday April 14, 2025 @08:36AM (#43680626)
fun to use. what could be the evolution of it?
Re:Show HN: Pintalk – Public, location-based chat rooms on a... by cracadumi on Monday April 14, 2025 @08:44AM (#43680682)
Thanks, glad you found it fun! That was the main goal for this initial version.

Good question on evolution. Some ideas that come to mind, building on the core location concept:

Ephemerality: Maybe messages could disappear after a set time (e.g., 24h via TTL indexes) to keep conversations fresh and less like permanent archives.

Discovery/Activity: A heatmap layer (using something like Leaflet.heat) showing areas with recent message activity could be interesting for finding active spots without needing to click every pin. Could aggregate message counts per pin/area on the backend.

Mobile: A native app could enable things like background notifications for nearby activity, but that's obviously a much bigger step.

Definitely open to other thoughts if people find the core idea engaging.

Re:Show HN: Pintalk – Public, location-based chat rooms on a... by tomemme on Monday April 14, 2025 @08:52AM (#43680753)
that's pretty cool, will dig around and see if any bugs revel themselves :)
Re:Show HN: Pintalk – Public, location-based chat rooms on a... by cracadumi on Monday April 14, 2025 @09:02AM (#43680823)
Thanks! Appreciate you taking a look. Definitely let me know if you spot any rough edges or outright bugs – feedback is very welcome.