There used to be a chain analysis tool called oxt.me (maybe don't visit that domain any more: it was a project from Samourai and who knows who controls the domain now).
Anyhow, I once had ambitions at honing my skills with it. It was pretty handy for tracking how coins moved from one address to the next.
Now it looks like someone has created a new chain analysis tool for Bitcoiners.
oxt.me had some really great visualizations that I loved and it doesn't seem like this tool has implemented something like that. So in a lot of ways it feels similar to mempool.space, but they describe a few differences in their about page:
Bithypha is an open and community-driven blockchain analysis tool based in the Netherlands. Our goal is to provide Bitcoin users with a blockchain analysis tool that has the same features you generally only find in paid tools made by large corporations. This way, we aim to empower Bitcoin users and make them aware of the implications and limitations of blockchain analysis tools, giving them insight into what they can do to improve their privacy (sometimes as simple as not reusing their addresses).
We would like to focus on building features that you currently only find in paid tools. For example, we recently released a feature to perform an auto-analysis on wallets and addresses, seeing all taint that occurred within a set distance from a wallet or address, this is something you cannot currently do with other open tools. In the upcoming time we will expand on this, allowing you to see all the transactional links between a certain taint and the address or wallet you scanned. We also do our best to give users as much attributions as we can find.
As with any tool not hosted on your own machines, you probably don't want to use it to search any addresses connected to you (unless you feel very confident in your vpn or tor).
How do they know there are Cashapp or Robinhood?
The difference with otx.me was that it made a nice visual link between addresses. Bithypha doesn't seem to do that (yet).
Most often this is done through input correlation and known cold address interaction. The heuristic is that:
coinjoins break the former, which is why many KYC exchanges will reject your tx when you coinjoin, because their analytics software doesn't work on it.
Exactly. Theirs is free as in beer, not as in willy.
i hadn't heard the willy variation before. at first I thought you meant something different than the dolphin...
I don't remember who I stole it from but do remember I thought the same, so it stuck.
There's an option at the bottom to "add a note" to an address.
Why would anyone want to do that? To dox someone, or?