Numo: Lessons From Standing Behind the Counter
For the last couple of months, we've been doing something we don't usually get to do: standing behind counters. Conferences, restaurants, actual merchants selling actual things. Instead of trying to orange pill or pitch Numo, we've been handing over the device, stepping back, and watching what happens. Then taking notes. Lots of notes.
For those unfamiliar, Numo is a bitcoin point-of-sale app that lets any merchant accept bitcoin payments, ecash or lightning, from any Android phone or device. We're building it to be the fastest way to start accepting bitcoin over the counter, without setup or bitcoin knowledge as a prerequisite.
Why merchants are different
Most of our background is on the consumer side: apps, retail flows, personal wallets, the stuff you use with one thumb while talking to other bitcoiners at a bar or conference. A merchant POS is a different beast. Merchants are at work. Efficiency, speed, and reliability are what matter most. They aren't enthusiasts here to tinker and troubleshoot for fun. They operate in a dynamic environment: the lunch rush is coming, a table all wants to pay for their beers at once and leave, the wifi is flaky, and the person holding the Numo POS got a thirty-second explanation of how to process payments. In that environment, every design decision gets stress tested by someone who doesn't know the difference between on chain, lightning, and ecash —and never will.
This reality has changed how we build Numo. Features we would have considered essential turned out to be noise. Things we'd never have thought of, like how pending payments clutter the activity view when connections drop, became obvious the moment we watched someone deal with it during a rush.
What we've changed
Most of the useful changes we've shipped over the course of the last few months have come from watching merchants work and listening to them telling us what they need, or spotting movements of frustration while looking over their shoulders.
Transaction logs aren't enough. Merchants need quick sale summaries. The sales summary groups money in by day, week, or month, switches between fiat and bitcoin, and shows which catalog items actually sold. That came directly from being asked which hat was selling best and having no fast answer.
We cleaned up activity and records. Pending Lightning invoices no longer need to dominate the history view: the new filter model hides or reveals them, adds date ranges, and keeps CSV export close by. We also rebuilt transaction details so balances, labels, withdrawals, and “Print receipt” live in one place instead of behind another screen.
We made transactions accountable. One of the earliest pieces of feedback we heard was also one of the most non-negotiable: merchants need to tag individual transactions and get those tags out of the app for their books. Merchants can now tag any transaction individually, and those tags flow straight into the CSV export alongside the rest of the record.
We reduced uncertainty during payment. BIP321 was a key factor here, unified payment QR. We also optimized for quicker NFC motion, clearer processing states, haptics, focused on helping to bring clarity to this common scenario: if a customer is waiting, the device has to make it obvious where they are and what they should be doing. Whether tapping, waiting, retrying, or success.
A constant battle is simplifying setup and mint selection. We want Numo to be the quickest way for a merchant to start accepting bitcoin. The technical properties of ecash are well suited for that, we just need the onboarding ux to catch up. Several onboarding iterations made the default mint clearer, removed unnecessary confirmation steps, and included optional explainers for tap-to-pay, auto-transfer to self-custody.
The best POS is the one you forget you're using
Features like transaction labeling and faster NFC reading are what actually matter to merchants. It's the difference between a POS a merchant tolerates and one they trust. Every change we've pushed has come from a real problem: bad Wi-Fi, a customer waiting, four items filling half the screen. The sales summary is a good example. Lisa, the founder of Bitcoin++, asked me which items were selling best, and I realized I had no quick way to answer. So we built one.
We think the best bitcoin POS is the one a merchant forgets they're using. The one that just works. Every update gets us closer, and we're going to keep shipping them. One PR at a time.
This article is a guest post by Erik.
