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Bitchat – A decentralized messaging app that works over Bluetooth mesh networks

(github.com)
778 points ananddtyagi | 6 comments | 07 Jul 25 00:05 UTC | HN request time: 0.632s | source | bottom
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moneywaters ◴[07 Jul 25 05:35 UTC] No.44487086[source]▶
I’ve been toying with a concept inspired by Apple’s Find My network: Imagine a decentralized, delay-tolerant messaging system where messages hop device-to-device (e.g., via Bluetooth, UWB, Wi-Fi Direct), similar to how “Find My” relays location via nearby iPhones.

Now add a twist: • Senders pay a small fee to send a message. • Relaying devices earn a micro-payment (could be tokens, sats, etc.) for carrying the message one hop further. • End-to-end encrypted, fully decentralized, optionally anonymous.

Basically, a “postal network” built on people’s phones, without needing a traditional internet connection. Works best in areas with patchy or no internet, or under censorship.

Obvious challenges: • Latency and reliability (it’s not real-time). • Abuse/spam prevention. • Power consumption and user opt-in. • Viable incentive structures.

What do you think? Is this viable? Any real-world use cases where this might be actually useful — or is it just a neat academic toy?

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jacobgkau ◴[07 Jul 25 05:42 UTC] No.44487126[source]▶
> Works best in areas with patchy or no internet, or under censorship.

The biggest problem I immediately foresee is that this sounds backwards. It doesn't work best in areas with patchy or no internet, it works best in areas with lots of participating devices. It's most needed in areas with patchy or no internet, but those areas are likely to be the opposite of the areas with lots of participating devices.

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Dr4kn ◴[07 Jul 25 06:23 UTC] No.44487298[source]▶
If your country shuts off Internet access for demonstrations this would work great.
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1. xyzzy123 ◴[07 Jul 25 07:24 UTC] No.44487588[source]▶
I guess it depends on the authoritarian government, but a sufficiently powerful one will get the app taken down or get the bluetooth features it relies on disabled (like for airdrop in China) :/

I would say that the underlying issue is that people do not really "own" their devices and the corporations that do are vulnerable to (or complicit in) state coercion.

You cannot truly have freedom on a non-free device, you can just be small enough to not be worth taking action against yet.

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2. synctext ◴[07 Jul 25 10:56 UTC] No.44488885[source]▶
Indeed! Advanced countries will and have blocked apps.

For a more extensive discussion on censorship resilient mesh networking, see IETF Internet Standard draft from 2012 [1]. After the Arab Spring there was global hope. Great to see revival of this topic today. Mesh networking is 1990s. The lesson from decades ago was that mesh networking can't be the killer use-case. Users need a reason to install this and allow it to drain the battery while looking for nearby nodes. Mesh networking never broke through the glass ceiling.

Blocking apps is real. Even Amazon killed a side-loaded app [2].

[1] https://www.ietf.org/archive/id/draft-pouwelse-censorfree-sc...

[2] https://torrentfreak.com/amazon-remote-disables-piracy-apps-...

3. thenthenthen ◴[07 Jul 25 17:44 UTC] No.44492824[source]▶
Airdrop works fine in China, actually, if you leave it open you will be harassed by unwanted drops in public transport. E-sims are not allowed.
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4. ChicagoBoy11 ◴[07 Jul 25 17:58 UTC] No.44492993[source]▶
wait timeout... airdrop is disabled in china?!
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5. xyzzy123 ◴[07 Jul 25 23:08 UTC] No.44495483[source]▶
Was a bit more subtle than "disabled" really. See: https://www.engadget.com/apple-china-airdrop-limit-everyone-...

I think you could reasonably argue that the measure limits Airdrop spam.

6. xyzzy123 ◴[08 Jul 25 02:01 UTC] No.44496311[source]▶
Yeah the change they made was to auto shut off airdrop after 10 mins. It's just that it happened to roll out in China around the same time that many apps were banned and protesters were reported as using airdrop to pass messages.

But I mostly agree - they rolled it out worldwide later on because once you reason it through, disabling it when it's not actively used turns out to be the better default.