Bringing Legacy Systems Into The Modern World

At Belly, we’re making businesses personal for every single merchant - no matter what. So here was a challenge: connect a 20 year old legacy POS system developed by a third party and running on an outdated operating system to the Belly Merchant app on iPad. This is what we were working with:


The devices needed to not only integrate but also establish a bi-directional communication channel, so that the iPad functionality would remain the way our Members have come to know and love.

So here’s what we did.

We connected the legacy system to the iPad using a standard USB to lightning cable. This would be our communication channel.


Our client was highly sensitive to making complex changes to the application running their POS system. Therefore, we developed a C++ library for the POS application maintainers to use which messages could be sent and received over. Doing this significantly decreased the burden placed on the merchant’s third party development team, too. On the iPad side, we implemented a similar library that allowed us to integrate this communication with our existing iPad app.

So how does this work in the wild? Through this communication channel, the POS system can notify the iPad each time an item is scanned. Take a look:


Now watch what happens on the iPad screen.


As you can see, the iPad updates immediately, showing the customer each item, total item count and total cost for the transaction.

Even if items are entered manually, the iPad remains in sync with the POS system’s record of the transaction.



What makes Belly’s integration with legacy systems so revolutionary is the fact that a bi-directional conversation is occurring, meaning that the iPad can also transmit messages to the POS system.


When a Member checks in on the iPad, their unique information appears on the POS visible to a sales associate so they can greet the customer by name, learn their Member Status and prepare for a potential up-sell opportunity.


Need help pulling your outdated POS out of the past and into the modern world? Learn more about BLUE by Belly here.

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