Working offline
A till that stops when the internet does is not a till. This is the single reason the desktop app exists.
What "offline" actually means here
The catalogue lives in a local database on the till. A sale completes instantly against that, prints its receipt, and joins a queue. When the connection returns, the queue drains into your SBB account.
Nothing waits on the network. There is no spinner between the customer paying and the receipt printing.
| Offline | Online | |
|---|---|---|
| Ring up a sale | ✓ | ✓ |
| Print a receipt | ✓ | ✓ |
| Take cash, MoMo, card, credit | ✓ | ✓ |
| Restaurant tabs | ✓ | ✓ |
| Request MoMo to a phone | — | ✓ |
| New products appearing from the web | — | ✓ |
A sale can never be recorded twice
The thing everybody asks about, and the thing a queue gets wrong.
Each queued sale carries its own identity. If the connection drops while a sale is syncing, the retry lands on the same record rather than creating a second one. Losing the reply is not the same as losing the sale.
You can watch it happen
The Logs screen shows what has synced and what is waiting. During a long outage that queue is the honest answer to "did that go through?".
Several tills in one shop
Two counters selling the same last item is the classic problem. On SBB Desktop the tills tell each other what they sold, over the shop's own network — no internet, no server, no configuration.
It works over a plain broadcast on the local network, which is why it needs no setup: a shop LAN is a single broadcast domain. Put two tills on the same Wi-Fi and they find each other.
This layer is advisory, and deliberately so
A lost message on the LAN is acceptable — the cloud still reconciles the truth. This exists to stop two counters selling the same last crate within seconds of each other, not to be the system of record.
If your two tills disagree for a moment, the books do not.
What happens on reconnection
- The queue drains, oldest first.
- The catalogue refreshes — new products, price changes, stock from elsewhere.
- The Logs screen goes quiet.
Nobody has to press anything.
Power cuts
The local database is on disk, not in memory. A till that loses power mid-shift comes back with its sales, its queue and its open tabs intact.
What to check when something looks wrong
| Looks like | Usually is |
|---|---|
| Sales not appearing on the web | Still queued — check Logs |
| A product missing at the till | Added on the web, catalogue not refreshed yet |
| Two tills showing different stock | One has been offline; the cloud reconciles |
| Scanner does nothing | The search box lost focus — click it |
Related
- Selling at the till — the daily job
- Receipt printers & hardware
- Working offline — offline across the whole product, not just the till
- SBB Desktop — the manual