The problem
There's a whole category of small business — the corner store, the family-run pharmacy, the neighborhood tailor — that wants the benefits of an inventory system without the cost or complexity of a desktop POS. Square is great if you're already a coffee shop in Brooklyn. It's a stretch for a shop in a developing market where the most reliable computer in the building is the owner's phone.
What it does
- Inventory in your pocket — add items by scanning, by typing, or by snapping a photo. Counts update in real time.
- Phone-as-register — ring up a sale, accept payment, print a receipt. The whole flow is designed for one hand.
- Daily summaries — at end-of-day, a single screen tells you what sold, what's running low, and what made you the most money.
- Offline-first — works even when the connection drops. Sync happens when you're back online.
How it's built
PHP on the server with a thin REST API, MySQL for persistence, and the front-end is a progressive web app — plain JavaScript, designed to be installable to the home screen and to function without a live connection.
If a feature didn't survive the "would my uncle use this?" test, it didn't ship.
Things I learned
The interesting work was almost all on the data model — handling refunds, partial returns, voided transactions, and stock adjustments in a way that left an auditable trail. You can build a basic POS in a weekend. Building one that doesn't lie to you about your own business is the hard part.
Where it goes next
I'd like to pilot it with two or three actual shopkeepers and see what they break. My bet is that the feature list will get smaller after that, not larger.