Berlin doesn’t need another social network.
Sometimes, though, it would be useful to talk to people who are actually in the same place at that exact moment. Before a concert. At a street festival. At a flea market. Or simply in your own neighbourhood. Not as a post that appears in a feed hours later, but at the very moment something is happening.
That idea became 030.berlin: a location-based voice chat for Berlin. Anyone in the city can join a district channel directly in their browser, listen in and use the push-to-talk button to speak live. There is no account, no download and no profile.
It works like a walkie-talkie: open the site, hold down the button, speak, release it and listen.
At first, that may sound like a small application. But its simplicity is built on a series of deliberate product decisions.
The starting question was: What can we leave out?
Many digital products begin with a list of features: user accounts, profiles, contacts, posts, comments, likes, notifications and as many opportunities as possible to analyse something later.
With 030.berlin, the more important question was: What does a spontaneous local conversation actually need?
The answer was short and simple:
- People who are currently in Berlin
- A shared channel
- A button to talk
Signing up would have slowed people down. A profile would have turned an ephemeral conversation back into a permanent identity. A feed would have shifted attention away from the present moment and towards content that had already been published.
That is why everyone automatically receives a random call sign such as “Currywurst36” when they open the site. A quick location check then selects the appropriate district channel. Anyone who would rather listen or speak citywide can switch to Channel 9.
A channel instead of a feed
On most platforms, communication is stored, sorted and rated. An algorithm decides which posts remain visible. Reactions and follower counts turn conversations into measurable content.
030.berlin works differently. Everyone on the same channel hears the same voice at the same time. Only one person can speak at a time, for a maximum of 60 seconds. Then the channel is free again.
The principle is not new. It comes from two-way radio. What is new is that it no longer requires a radio. A modern browser on a smartphone or computer is enough.
This form of communication is intentionally ephemeral. 030.berlin does not record conversations. There is no archive and no history. Said, heard, gone.
That does not make an open voice chat a private space. Other people on the channel could record it at any time. That is why 030.berlin uses call signs instead of real names and clearly advises people not to share personal information. Here, privacy does not begin with a reassuring label, but with a boundary everyone can understand.
Local, without creating a location history
A Berlin channel only makes sense if the people using it are actually in Berlin. That is why 030.berlin checks a person’s location once when they join and selects the appropriate district at the same time.
The coordinates are used only for this check and then discarded. They are not stored, logged or shared with third parties. The IP address is processed for a limited time to establish the connection and prevent abuse, but it is not used to create a permanent user profile.
This distinction matters. Data minimisation does not mean pretending that a web app needs no technical data at all. It means processing only the data required for a specific function and not collecting it in advance for potential future purposes.
Easy to use does not mean easy to build
The visible interface essentially consists of a channel, a level meter and a large push-to-talk button. Behind the scenes, however, several things have to work together reliably:
- Voice is transmitted live to everyone on the same channel.
- The microphone transmits only while the push-to-talk button is held down.
- Switching channels and moving between speaking and listening must work instantly.
- On supported devices, the connection continues even when the screen is off.
- Controls appear on the lock screen.
- Shared links open the desired channel directly.
- Reports, temporary bans and a maximum speaking time help limit abuse.
There are also twelve district channels, one channel for all of Berlin, a German and an English interface, and the option to use 030.berlin as an installable web app without going through an app store.
Why the interface looks like a radio
The radio-inspired design is more than a nostalgic visual idea. It explains how the application works before anyone has read a set of instructions: select a channel, hold the button, speak and release it.
The S-meter and segmented display are not merely decoration either. They show the actual audio level and the selected channel. Form follows function, while also giving 030.berlin a character of its own.
Good digital products do not have to look like yet another dashboard. Sometimes, a familiar interface is the shortest instruction manual.
The real challenge is not technical
An open channel only becomes interesting when several people are listening at the same time. That is the central challenge of any real-time platform.
A conventional social network can disguise quiet periods with old posts, recommendations and an endless feed. That is exactly what 030.berlin is designed not to do. If nobody is there, the channel remains silent.
That is why channels can be shared directly as links. If requested, the web app sends a notification as soon as several people become active on a selected channel. Both features help bring people together at the same moment, without introducing an artificial feed or permanent user profiles.
Whether 030.berlin will be used mainly at events, around the neighbourhood or in entirely different situations will only become clear over time. For me, that uncertainty is also part of the appeal of creating an independent digital product: an idea is not merely described, but developed far enough for real people to try it.
What 030.berlin shows about good web apps
030.berlin is not a typical client project. Even so, the platform gives a clear picture of how I approach custom web apps.
Not every application needs a user account, not every piece of information needs to be stored and not every digital product belongs in an app store.
What matters is what people want to do in a specific situation. That determines the features, the data flows and the right interface. Anything that gets in the way is removed.
Berlin is live
030.berlin is free, ad-free and works directly in the browser. Anyone currently in Berlin can open the site on a smartphone or computer, briefly confirm their location and listen in.
Maybe someone is already on Channel 9.
