Straight answers on how the change is held, what stops misuse, what happens when the network drops, and which shops Marii Cards is actually for.
No value ever sits on the card — it is an identifier. Every cent lives in a ledger with a full audit trail, so a lost card loses nothing: the customer blocks it in seconds, staff link a replacement and what was on it is exactly where it was.
Spending needs proof it is them: the signed code on their own phone, or their card and their PIN — checked by our servers, never stored on your till. A phone number alone can receive change but never spend, and a photocopied card is useless without the PIN.
The till keeps working. Keeping change, and spending with the code on the customer’s phone, both work offline — transactions queue on the device and send themselves when the signal returns. Spending by card needs a connection, because the PIN is checked by our servers and never kept on the till.
No. The SMS they receive links to what you are holding for them, in the browser — every card they hold, and a code to pay at the till. It works on any phone with a browser.
No. Change kept is not exchangeable for cash and not transferable — it is spent at your till, on your goods. That is the point.
Yes. Post a special with your own poster and every customer whose change you hold sees it in the app, unless they have asked you to stop. Customers who agree at your till can also get it by text, from your text allowance — straight to their phone, no algorithm deciding who sees it. Three specials can run at a time.
It is built for shops customers already return to — the neighbourhood supermarket, the butchery, the pharmacy. If your trade is one-off walk-ins, this is not your product, and we will tell you so.