PearTune

Your phone talks straight to the machine holding your music. There is no PearTune server in the middle, no copy of your library anywhere else and no account. Nothing on that machine is exposed to the internet, so there is nothing there for anyone to find.

Playing music that lives on your own computer is easy at home and awkward everywhere else. The traditional answers all amount to making your machine reachable from the internet: forward a port on your router, run a VPN, or pay for a service that keeps track of your changing home address.

Each of those works, and each of them means something in your house is now listening to the whole internet, and you are responsible for it staying safe. For a lot of people that is the reason their music collection stays at home.

PearTune takes the other route. Rather than making the machine reachable, it has both ends reach out and meet in the middle. Nothing on your network is opened, and there is nothing to secure afterwards.

PearTune is built on the Hypercore Protocol, the same peer to peer foundation the other PeerLoom apps use.

When you pair a phone with a library, both sides learn a long random identifier for the other. Later, each one announces to a shared network of peers that it is looking for that identifier, and the two are put in touch. Both then make outgoing connections towards each other at the same moment, which is what lets a connection form without either side accepting incoming traffic. It is the same technique that lets a video call connect without you configuring anything.

Nobody in that network of peers learns who you are or what you listen to. The identifiers are random numbers, not names, and everything that flows once the connection is up is encrypted.

Most self-hosted media servers give you an account, or a long link that anyone holding it can use. Both are things that can be shared by accident, copied out of a message, or left working long after you meant them to stop.

PearTune has neither. Every connection is authenticated with cryptographic keys generated on the devices themselves, so the library knows precisely which phone is asking before it answers, and the phone knows it has reached the right library. Your phone's key never leaves your phone.

That has a pleasant consequence: taking access away is exact. Removing a device on the dashboard cuts that one device off, immediately, including one that is connected and playing at that moment. Nobody else is disturbed, nobody has to change a password, and there is no shared secret still floating around afterwards.

On the machine holding the music: the files, an index of them, the list of allowed devices, the names people chose, and per-person listening history such as favourites, play counts and where you got to in a track.

On your phone: its own identity key, the queue you are playing, anything you downloaded for offline listening, and your preferences.

On PeerLoom's servers: nothing. There is no account, no profile, no library index and no listening history, because there is nowhere for it to go.

Direct connections work on the large majority of networks. On some, particularly certain mobile networks, the two ends cannot reach each other at all no matter how patiently they try. Without a fallback, those users would simply never connect, and would have no way of knowing why.

So PearTune can fall back to a relay that PeerLoom runs, which forwards the traffic between the two ends. It is genuinely a last resort: a direct connection is always attempted first, and the relay is only used when that fails.

The relay cannot read anything it carries. Traffic is encrypted end to end between your phone and your library, and PeerLoom holds no key to it. What a relay unavoidably handles is that two ends are talking, identified by random keys rather than names, plus timing and volume. It stores none of that.

You can switch it off in the app's settings. With it off, PearTune is purely phone to library, and on those few networks it will not connect. Full detail: The PeerLoom relay.

Worth saying plainly, because no design is free.

• Something has to be on. There is no cloud copy, so if the machine is asleep, streaming is unavailable. Downloaded music still plays.
• The first connection can take a few seconds when you are away from home, because the two ends have to find each other rather than dialling a known address.
• Someone has to run the library. That is a real job, even a small one. It does not have to be you, which is the point of letting friends in.
• A library owner can see what you play from their collection. That is inherent to their machine serving you the files, and it is what makes resume points and listening history work.

What you get in return is that your music stays yours, on hardware you or someone you trust controls, with no company in a position to lose it, mine it or switch it off.

Both the app and the server software are open source, so none of the above has to be taken on trust. Read it at github.com/peerloomllc/peartune.

• PearTune privacy policy
• Setting up a server
• The PeerLoom relay