MAP Forum

I mean, in a more effective way than talking to individual people and hoping to find someone who lives close to you.

My idea is that the apps for contact-tracing that were deployed during the last pandemic achieved the following:

• If you were close to someone with the virus, an alert would arrive days later at your phone.
• It uses bluetooth, so no central server will know which people you interacted with.
• You don't know which of the people you were close to had the virus.

If, additionally to the alert, you could also get a nickname (or some similarly small piece of information) of the "infected" person that was close to you, without revealing their real identity, then you will be able to communicate with them and perhaps a community would emerge from there.

So the issue is that I don't have knowledge about the implementation, so I don't know if this is actually possible. The idea would be to have an app whose intent were to help people with shared interests meet safely, but it would have to be used for a multitude of interests, not a single one, as otherwise you'd know why someone is using the app, thus defeating the purpose. If you were close to someone with a shared interest, you'd receive a notification a few days later. Ideally, the available interests would not be controlled by a central server, thus making the app censorship-resistant.

So I am not sure, does anyone who know about technology and privacy have any feedback? Is this possible? Would privacy be compromised? Has it been tried? Would there be problems with people using it for shady purposes?

Sounds a lot like the Nintendo 3DS's Street Pass feature.

RoosterDance wrote: Mon Mar 09, 2026 6:47 am Sounds a lot like the Nintendo 3DS's Street Pass feature.

Interesting. I didn't know about it. I wonder why the feature was not added to the Switch. And how private it was.

A few years ago I suggested a similar idea to Ketzerscriften (a German-speaking MAP Blog) I advised to use an a app called "Briar" that works like that and it was used in Hong Kong 2019-2020 protests, they didn't did anything with that ideas as it happened many times in the past.

HumanBeing wrote: Mon Mar 09, 2026 10:08 pm as it happened many times in the past.

What do you mean? The idea had been tried in the past?

It probably wouldn't work without modifications for your aims, but Meshtastic and Meshcore are worth checking out. Really depends on the local infrastructure and how many people have nodes set up between you and the person you want to contact, but you have fully end to end encrypted messaging capabilities sent over radio signals. The data limitations of radio technology even create a wall of inherent safety against PIM (and the legal trouble they bring) because you can't send images. The only problem is that it seems mostly set up for individual chats between but since the code is open source it's theoretically possible to achieve some form of what you want.

Learning to undeny wrote: Tue Mar 10, 2026 12:18 am

HumanBeing wrote: Mon Mar 09, 2026 10:08 pm as it happened many times in the past.

What do you mean? The idea had been tried in the past?

No, I mean that my ideas are usually ignored by the community, in the past I shared some ideas to help activists and the community but no one cares

Scorchingwilde wrote: Tue Mar 10, 2026 3:34 am It probably wouldn't work without modifications for your aims, but Meshtastic and Meshcore are worth checking out. Really depends on the local infrastructure and how many people have nodes set up between you and the person you want to contact, but you have fully end to end encrypted messaging capabilities sent over radio signals. The data limitations of radio technology even create a wall of inherent safety against PIM (and the legal trouble they bring) because you can't send images. The only problem is that it seems mostly set up for individual chats between but since the code is open source it's theoretically possible to achieve some form of what you want.

That's very interesting. I'd say the precondition #1 is convenience and ease of use, because otherwise it's impossible to convince people to use the system. So ideally it would be just a free, multi-platform app available for smartphones. (If I understand, Meshtatic and Meshcore require special radio hardware, a bit more than I would want, but it looks like a nice solution apart from that.)

Also, Briar seems to be focused on communicating between people who already know each other, whereas what I'm proposing would be used to make contacts. At least if I understand correctly.

So the idea is that nearby phones with the app exchange random codes and then the codes are published. Together with the codes, a secret key could be exchanged so that one can upload a piece of information with the code.

However, I'm open to different solutions as long as they have a chance of adoption.

HumanBeing wrote: Mon Mar 09, 2026 10:08 pm A few years ago I suggested a similar idea to Ketzerscriften (a German-speaking MAP Blog) I advised to use an a app called "Briar" that works like that and it was used in Hong Kong 2019-2020 protests, they didn't did anything with that ideas as it happened many times in the past.

OK, I've just installed the app Briar and it might be worth giving a try, if anyone has a clear plan to make contacts. Also, I only have 1 phone to try at the moment so I don't know what happens when it detects a nearby phone with the app. I do find advantages in the other solutions offered that rely on radio communications, but as I said, ease of installation and use is the killer feature in my opinion.

Learning to undeny wrote: Tue Mar 10, 2026 1:30 pm So the idea is that nearby phones with the app exchange random codes and then the codes are published. Together with the codes, a secret key could be exchanged so that one can upload a piece of information with the code.

Probably this didn't make much sense as we would not gain anything over simply adding the contact in real time.