Offline & Online POS

A Flutter point-of-sale app for fast counter billing: items, cart, taxes and payment in a few taps. It works the same with or without internet, so a slow or dropped connection never holds up a sale.

The client needed to run the POS even without internet. Their counters couldn't stop selling whenever the network was slow or down, but a POS that waits on the server for every bill turns low bandwidth into a queue at the counter, and no connection into lost sales.

Built the app end to end: Flutter development and the offline sync

The app was built to work offline first. Every bill is completed and saved on the device without waiting for the network. When a connection is available, sales sync to the server in the background, so the cashier works the same way whether the connection is strong, weak or gone.

The counter keeps billing on a weak connection or with no internet at all, so a network outage no longer means a queue or a lost sale. Sales made offline sync to the server once the connection returns.