What others can see
Paying with bitcoin does not require the customer to send a name or bank account number with the payment. It still creates a public transaction. Anyone who knows the payment address or transaction ID, its identifying number, can look up the movement of bitcoin and follow links to other transactions.
A customer knows the address used for their purchase. An exchange knows the deposit you send it. A person who connects an address with your shop may be able to learn more than the amount of one sale. OpenBMT limits what it shares, but does not make the shop’s activity invisible.
The main contacts
| Who | What it can learn |
|---|---|
| Customer | The address and amount for that purchase. |
| POS vendor | Its orders, prices and the fact that a Bitcoin payment type was used. OpenBMT does not put wallet addresses or transaction IDs in those fields. |
| Bitcoin peers | Computers used for payment checking can see the counter’s network address and which blocks it requests. |
| Price sources | That a device requested a price and when. They receive no sale or wallet address. |
| Someone hosting a Box for you | Order amounts and timing, enough to estimate activity using the public bitcoin price. |
| Exchange | The deposit and the incoming payments linked when you spend them together. |
The network reference lists every contact and the exact data exposed. OpenBMT sends no analytics or crash uploads to its publisher. Push wake-ups and a hosted Box service are not built yet.
A fresh address helps, but is not a private account
OpenBMT uses a new address for each sale. That prevents every customer from seeing all receipts at one reused shop address. The transaction record remains public, and later spending can link the receipts.
Suppose you receive several purchases, then send their bitcoin together to an exchange. That one transaction links the incoming payments. A customer following their own payment, or the exchange receiving the transfer, can see the association. Consolidating small incoming payments has the same effect. The app warns when it offers a merge.
Wallet software can also leave recognizable patterns in the transactions it builds. OpenBMT does not claim to hide which software created its transactions. The fingerprint reference links a detector for readers who want to inspect that issue.
What Tor changes
Tor routes connections through other computers so the destination does not see the phone’s ordinary network address. It does not hide the public Bitcoin transaction. It also does not turn an unconfirmed payment into a reliable one.
The Counter app’s Tor switch covers its Bitcoin and price connections. It is off by default for speed. If customers can join the counter’s network, instant acceptance requires Tor, because a customer on that network could feed the counter false information. The Owner app sends its Bitcoin peer traffic and broadcasts of spends and refunds through Tor, with no switch to turn that off. An explicitly configured local link between shop devices can run directly over the local network.
Both apps need Orbot, a separate Android app, to use Tor. If Orbot stops answering, the Owner app will not start and a counter with Tor enabled will not send around it. This is a real operating dependency: turning Tor on requires keeping Orbot running.
Checking through your own node
A full node checks the Bitcoin rules on a computer you run. OpenBMT can add its report to the counter’s own light check. It does not replace that check or remove the need to wait for confirmations under the shop’s policy.
The current own-node connection requires a Tor v3 address. This address also helps establish that the counter has reached the intended node. The network reference explains the connection restriction and why the counter retains its own chain checks.
Who runs the Box matters
The Box relays messages and reads POS orders. Device messages are encrypted so only their intended recipient can read the contents. The Box has no wallet key, wallet description, address or transaction ID. It can still see order values and timing. Someone else running it can estimate how much the shop sells.
Running it yourself keeps that information inside the shop. The Box can be reached on the local network or through a Tor address. A hosted Box service is not built yet.
Give the accountant the accounting export
The ordinary accounting export uses sale IDs that do not reveal a blockchain transaction by themselves. It excludes wallet addresses, transaction IDs and bitcoin amounts in satoshis. The full ledger does contain those details and is placed behind a warning. Choose the file that fits the recipient’s job rather than sending every wallet detail with the accounts.
The network reference also explains block-request patterns, encrypted peer connections and transaction fingerprints. These are limits on what observers can learn, rather than a promise of anonymity.