Why a till must keep selling when the internet drops

A queue at the counter does not pause because the router light has gone red. For a shop, a pharmacy or a restaurant, the question is not whether the connection will drop but what the till does for the twenty minutes while it is down. "Offline-first" is the name for software that treats the local device as the place a sale is made, and the cloud as the place it is reported. The difference is visible the first time the line goes.

What offline-first means in practice

A cloud till that merely runs in a browser needs the server for every action: adding an item, taking payment, printing. When the connection drops, the screen spins and the cashier starts writing on paper. An offline-first till keeps a local copy of what it needs to sell (products, prices, customers, staff, taxes and payment accounts), writes each sale to local storage first, and sends it on when it can.

Kit's own desktop till is published this way. The download page at pos.kit.africa describes Kit POS Desktop as an offline point of sale and currently lists release 3.4.2 for Windows as a 189 MB installer dated 1 October 2026, alongside the earlier 1.0.0 builds. After the first online login the app pulls the business data for the chosen location, and selling continues without a connection.

Four things to test before you trust it

Marketing claims are cheap. Switch off the Wi-Fi on a quiet afternoon and run through this list.

1. Can you complete a cash sale and print the receipt? Receipt printing should not depend on the server. Browser-based tills typically print through a local bridge such as QZ Tray, which its publisher describes as running on Windows, macOS and Linux and supporting ESC/POS receipt printers over USB, serial and network connections.
2. Can you make a credit sale to a known customer? The customer list must be on the device.
3. What happens to the sale when the line returns? It should sync without anyone pressing a button, and the office should be able to see how many sales each till still has waiting.
4. What if the till is restarted or a different cashier logs in before sync? Queued sales must survive both.

If any of the four fails, you do not have an offline till; you have a web page with a cache.

Mobile money is the exception

One thing cannot be done offline: confirming a mobile money payment. The payment prompt reaches the customer's phone through the operator, and the till needs a connection to learn that the payment succeeded. The sensible rule for an outage is cash and credit sales only, with mobile money payments taken on the operator's own app and recorded against the sale once the till is back online. Train the cashier on this before the first outage, not during it.

Local data is not a backup

An offline till holds a working copy, not an archive. The NCSC's guide for small organisations recommends backing up "all the data that your business needs to operate", keeping a storage device disconnected when not in use and knowing how to restore. For a till that means the cloud account remains the record of truth, the till syncs to it as often as possible, and nobody treats the laptop under the counter as the only copy of September's sales.

Power is the other half

Internet outages and power cuts often arrive together. A desktop till on a laptop keeps running on its battery; a desktop PC does not. If you run a tower PC, a small UPS that carries the PC, the router and the receipt printer for the length of a typical cut costs less than one afternoon of lost sales. Put the router on the UPS as well: a till with power but no router is still offline.

What to tell the office

The best outage is one the owner does not notice until the report. That requires two things: a till that queues honestly and an office view that shows the queue. Reconcile the day's sales against the cash drawer and the mobile money statement after sync, not before, and keep the paper fallback for the day the hardware itself fails.

Sources

1. https://pos.kit.africa/pos-desktop
2. https://qz.io/
3. https://www.ncsc.gov.uk/collection/small-organisations-guide-to-cyber-security/backing-up-your-data