Neopay
Replacing 500 Legacy POS Terminals with a High Performance Android App for Field Operations



Company
Flexpag, a fintech subsidiary of Serasa Experian, offers tailored electronic payment solutions through an integrated platform, serving sectors such as Energy, Water, Gas, Telecom, DMV, and Government.

Client
Neoenergia is one of the major players in the energy sector in Brazil, boasting assets for distributing, generating, transmitting, and selling energy in 19 Brazilian states.
Leading the digital transformation from legacy command-line terminals to a high-performance Android ecosystem.
During my tenure, the company saw its…
Problem
The company relied on an obsolete fleet of 500 POS devices that operated on text-only command lines. This legacy infrastructure created significant operational bottlenecks, high error rates during utility billing, and a poor experience for field consultants who struggled with a slow, non-intuitive interface.
Challenge
Design an Android POS application that takes full advantage of the device’s hardware, including the built-in camera and printer.
The solution needed to provide a fast, intuitive workflow to help operators deliver services efficiently, even under time pressure.
Accessibility was a key concern, as the app would often be used outdoors, in bright sunlight and by users with varying levels of digital literacy.
Understanding the
Current Product
Auditing the legacy command-line interface revealed that the absence of visual affordance created high cognitive load for operators, directly contributing to transaction errors and slow service times. Rather than iterating on the existing system, I treated this as a complete product rebuild from the ground up.
Old - POS Verifone VX680 (500 units)

New - POS Gertec GPOS 700 (3.000 units)
Competitors Analysis
Through a comparative analysis of market leaders like Stone and Cielo, I identified key functional gaps that shaped our product strategy.


Stone and Cielo LIO are the most common POS devices in the Brazilian market, they are dedicated devices for making payments.


Mercado Pago and Picpay are apps for smartphones that can be installed by any user, with payment functions and other services.
Analysis Finds
Extensibility: While competitors allow third-party app installations to expand device functionality, they lacked a specialized flow for utility sector operations.
Transaction Flexibility: I discovered a significant friction point in existing solutions, none supported multiple cards or split payment methods within a single transaction.
Utility-Specific Gaps: Although most players support standard bill payments (boleto) and PIX, none offered a native, direct integration for energy bill settlements, which became our primary competitive advantage.
User Interviews
4 in-depth contextual interviews, internal operators and external field consultants.
To validate our market assumptions, I conducted in-depth interviews with four key users, including both internal Neoenergia operators and external field consultants.The idea was to gather insights into their experiences and needs.

"The POS is very slow and sometimes crashes, so taking a long time to serve the customer."

"I am unable to confirm the past payments on the POS beyond the printed receipt."

"The device does not have a camera to read the barcode or QR-Code."

“ I have to pick up one account at a time, so taking a long time to complete customer service”.

"We don't have the possibility to pay with more than one card or other payment methods".

“I can't cancel a purchase through the POS, I have to call the company to cancel it”.
Key takeaways
Environmental Constraints: Users reported that the current devices frequently crashed and were nearly impossible to read under direct sunlight.
Hardware Friction: The lack of an integrated camera for barcode scanning forced a manual, error-prone entry process.
Process Rigidity: The inability to cancel transactions directly on the POS or use multiple payment methods was a major bottleneck in customer service.
Personas
Based on the gathered insights, I developed two distinct personas to guide our design decisions and ensure the solution addressed specific environmental and operational needs.

Manoel Marcos
External consultant
An external consultant who visits customers' residences to inform them about their outstanding debts.
Pain Point
Do not have the capability to provide customers with an instant payment method.


Camila Beatriz
On Place Consultant
Neoenergia employees are conveniently stationed at established service centers, providing expert consultation and facilitating energy bill payments.
Pain Point
Would like a portable device equipped with all the necessary functions to help customers check and pay their energy bills.
Prioritizing
With the essential features discovered in research and some already defined by the client, we came up with a roadmap with what would be delivered on MVP and upcoming versions.

Prioritizing - Now / next / later
V1
MVP
Payment options: debit card, credit card, PIX, and cash.
Ability to scan barcodes from multiple slips and pay in a single transaction.
Energy bill consultations with the option to print and/or pay the bill.
Feature to enable and disable transactions.
Money transfer capabilities.
Transaction cancellation.
Notification center for updates and alerts.
V2
PIX installment payments (currently being developed in another company product).
Ability to use multiple payment methods in a single transaction.
Option to pay with more than one card.
Help Center for customer support.
Various additional services.
Option to apply discount coupons.
Sitemap
I designed the sitemap to provide a bird’s-eye view of the entire ecosystem, ensuring a logical flow that accounts for the project’s depth. The goal was to maintain a flat hierarchy, allowing field consultants to navigate from the home screen to a completed transaction in the fewest taps possible.

Design System Foundation
I established an atomic design system with semantic tokens, ensuring that the interface remained consistent and accessible across 3,000 devices, significantly reducing engineering friction during handoff.


Design and Core Features
The final solution is a high-performance interface designed for the rigors of field operations. By leveraging the Android POS hardware capabilities, I created a seamless bridge between complex utility data and an intuitive touch experience.






Scanning of payment slips


Credit card

Debit card

Cash

PIX

Notification center


Money management

Money transfer
Impact and Retrospective
Impact
During my tenure, Flexpag scaled its monthly revenue from R$350K to R$90M and grew its workforce tenfold. The Neopay project was central to this trajectory, establishing the product foundation, design system, and UX architecture that enabled the company to deploy 3,000 new Android POS devices across Neoenergia's network.
What I learned
This project reshaped how I think about design in high-stakes operational environments. Three things stood out: first, that designing for field conditions (sunlight, time pressure, variable digital literacy) demands constraints-first thinking before aesthetics. Second, that a well-structured design system is a business asset, it directly reduced engineering friction at handoff. Third, that competitive analysis in a niche market isn't about features, it's about identifying the one gap no one else has solved. For Neopay, that gap was native utility bill integration.






