Mobills, Open Finance and AI: Lessons for UK Businesses

Mobills has resurfaced among the most searched topics in Brazil, and for good reason: the personal finance app has become a showcase for three technologies reshaping how businesses handle money — Open Finance, artificial intelligence and WhatsApp-based service. In this post, you'll understand what changed at Mobills and, more importantly, what its strategy teaches your business.

TL;DR

• Mobills uses Open Finance to sync accounts and cards automatically, without asking for bank passwords.
• Brazil already has over 128 million active Open Finance consents — the largest ecosystem in the world.
• AI delivers a "day-one financial diagnosis" and already operates inside WhatsApp as an assistant.
• The same building blocks (open data + AI + WhatsApp) are within reach of any business wanting to automate billing, reconciliation and customer service.
• At the end, I list common pitfalls and a practical path to apply this without becoming enslaved to spreadsheets.

What is Mobills and why it's booming again

Mobills is one of Brazil's best-known financial control apps. In practice, it centralises bills, expenses, income, credit cards and goals into a single monthly dashboard with charts, category filters and cloud sync. The free version covers the basics; Premium, which costs under £1.20 per month according to the official website{target="_blank"}, unlocks bank integration and advanced reports.

So far, nothing new — the app has been around for over a decade. What reignited interest was the combination of features. When Mobills connects a user's account via Open Finance, applies AI to that data, and lets the user chat with an assistant via WhatsApp, it stops being "a pretty spreadsheet" and becomes a decision system. That package is worth studying, even if your company never launches a finance app.

Open Finance: the invisible engine behind Mobills

The feature underpinning Mobills' automation is Open Finance, the system regulated by the Central Bank of Brazil{target="_blank"} that allows customers to share their own financial data between institutions. With explicit authorisation, Mobills receives transactions from accounts and cards without anyone having to enter a single entry manually.

The numbers explain why this has become standard. In January 2026, Brazil led the global ranking with 128 million active consents{target="_blank"}, with later reports pointing to over 150 million and more than 100 million connected customers. The ecosystem completed four years as the world's largest in the segment.

Two technical details of Mobills deserve attention because they apply to any similar integration:

• It is not retroactive. Synchronisation starts from the month consent is given — old history remains out.
• Each account and each card is connected individually. There is no "pull everything at once"; it's one consent per source.

And, according to Mobills' own documentation, the app never asks for or stores the bank password — access goes through the regulated layer, and the user can revoke it at any time. From a product-building perspective, this is gold: you get the data without inheriting the risk of storing third-party credentials.

It's worth understanding why this number of consents grew so fast. Between 2024 and 2025, the number of unique consents advanced more than 140%, a sign that sharing data has moved from exception to behaviour. For Mobills, this means an ever-larger base of accounts ready to connect in seconds; for the market, it means that Brazilian users have already normalised authorising the use of their own data when they see a clear benefit. Anyone offering financial services today competes for the attention of a user who already understands consent — and expects it to be worthwhile.

Who builds the technical bridge

Mobills does not talk to each bank individually. The integration is mediated by an Open Finance infrastructure — in this case, Belvo{target="_blank"}, which acts as a connector between the app and the institutions. That's architecture lesson number one: instead of reinventing dozens of bank connections, you contract a layer that already solves the standard. The same logic of "use the official API instead of a workaround" that we advocate for WhatsApp applies to financial data.

The AI turning point: diagnosis on day one

With the customer's history available right after consent, Mobills started delivering a near-immediate financial diagnosis. In the words of a company director, "on the first day the customer downloads, they already receive a financial diagnosis of their life" — something unthinkable when it depended on the user manually entering every expense.

Mobills' AI doesn't stop at diagnosis. The company reports using artificial intelligence to categorise NPS evaluations internally and, in partnership with Monetus, launched Mobills Investimentos{target="_blank"}, a platform that uses AI to suggest personalised investments and reshapes itself according to investor behaviour. It's the difference between recording the past and guiding the next decision.

For business owners, the takeaway is direct: raw data alone is worthless. What generates value is the interpretation layer on top of it. If you already collect orders, messages or payments, you're probably sitting on the raw material for a "day-one diagnosis" and haven't put AI to work yet. We talk more about this in the post on what changes with AI agents for businesses.

Mobills on WhatsApp: when the app becomes a conversation

The detail that most interests the Agathas Web audience: Mobills offers financial control directly via WhatsApp, chatting with an AI assistant. The user sends "I spent £30 on lunch" and the entry goes in automatically. This is not a gimmick — it's the recognition that WhatsApp has become the default interface for Brazilians, including for finances.

This is exactly the frontier we discussed when comparing WhatsApp Business App vs the Official API. An assistant that records expenses, responds to balance queries or sends payment reminders at scale is only viable on the Official API — the standard app cannot sustain serious automation or multiple agents without risk of being blocked.

The table below summarises the three layers that make Mobills work and how each translates to a common business:

Layer in Mobills	Underlying technology	How to apply in your business
Automatic account sync	Open Finance (Central Bank + connector)	Pull statements and reconcile payments without manual entry
Diagnosis and insights	Artificial intelligence on the data	Forecast cash flow, flag late payments, suggest actions
Log and query via chat	AI assistant on WhatsApp (Official API)	Automated billing, payment reminders and financial support

What Mobills' strategy teaches your business

You don't need to compete with Mobills to benefit from its playbook. The lessons apply to anyone selling services, running a school or managing an e-commerce business:

1. Eliminate manual data entry before dreaming of AI. Mobills' differentiator started when data began flowing in automatically. Automating capture is the prerequisite; without it, AI only processes gaps.
2. Treat financial data as an asset, not a file. Reconciled statements become cash flow forecasts and late payment alerts. The value lies in interpretation, not storage.
3. Meet customers where they already are. Mobills went to WhatsApp because that's where Brazilians chat. Billing, reminders and financial support perform much better on the same channel.
4. Use regulated and official layers. Open Finance for data, Official API for WhatsApp. Shortcuts outside the standard save you at the start but cost dearly later, through blocks or data breaches.

How to apply these ideas in your company

The practical path starts small. Don't try to build an "internal Mobills" in the first month. Choose one financial process that currently consumes time — typically billing or reconciliation — and tackle only that.

An automated billing flow, for example, combines all three layers: the system identifies the overdue payment (data), decides the timing and tone of the message (AI), and sends it via WhatsApp with an option for a payment link (conversation). It's the same principle as Mobills, applied to your accounts receivable. For teams that handle high volumes, it's worth understanding why paying per agent on WhatsApp no longer makes sense when automation handles the repetitive volume.

At Agathas Web, this is exactly the kind of integration we build: connect the data source, plug in an AI layer that decides, and deliver everything via the WhatsApp Official API with Voyia. Mobills proved the model works for millions of individuals; the same architecture scales to your finance department.

A common mistake is thinking this automation requires a huge data team. It doesn't. What it requires is clarity about which decision you want to automate. "Notify the customer three days before the due date" is an objective rule that AI executes without hesitation; "improve customer relationships" is not — it's too vague to become automation. After more than fifteen years delivering integrations for clients in Brazil and abroad, I can say that successful projects start with a small, answerable question, not an entire platform designed at once. Mobills also started by solving a specific problem — recording expenses without pain — and only later stacked layers.

Common pitfalls when automating finances

Before integrating everything, here are some stumbles I see frequently in real projects:

• Automating a broken process. If reconciliation is already wrong manually, automation only speeds up the error. Fix the process first.
• Ignoring consent. Open Finance and the Data Protection Act 2018 require explicit, traceable authorisation. Pulling data without a clear legal basis is a liability, not a shortcut.
• Confusing chatbot with assistant. A menu of options is not AI. A useful assistant understands natural language and acts — the rest frustrates the customer.
• Choosing the wrong WhatsApp channel. Running billing automation on the standard app is asking to be blocked. Volume and proactive messaging require the Official API.
• Stopping at diagnosis. A pretty report that nobody acts on is decoration. The goal is automatic decision-making, not another dashboard.

Conclusion: Mobills is the map, not the destination

Mobills grabbed attention because it combined Open Finance, AI and WhatsApp into a package that makes sense for the average user. But the valuable part for business owners is not the app itself — it's the playbook: capture data automatically, interpret it with AI, and converse on the right channel. That same tripod can automate your billing, reconciliation and financial customer service.

If you want to transform your company's finances from a reactive spreadsheet into a system that decides, start by mapping which process consumes the most time today. That's where automation pays for itself — and it's exactly the kind of integration we help build at Agathas Web.