A scam targeting her grandmother became the unexpected starting point for Rita Barbosa’s mission to make smartphones safer for people most vulnerable to fraud. What began as a deeply personal experience has evolved into Guardian Labs, a Portuguese startup developing Guardião, an AI powered layer designed to identify and block fraudulent calls and messages before users are exposed to them.
The company’s approach is deliberately different from conventional spam filters. Instead of warning users after a suspicious interaction has already reached their phones, Guardião aims to act as a first line of defence, operating quietly in the background.
From Family Scam to Startup
Barbosa’s grandmother was manipulated by scammers who falsely claimed that the water she was drinking was unsafe and that she was putting her family at risk. Believing the story, she purchased four water filters for around €1,000 each, despite their actual value being dramatically lower.
The financial loss was only part of the damage. The experience undermined her confidence in using technology and eventually made her reluctant to answer the phone.
That experience prompted Barbosa to explore whether technology could protect people without requiring them to identify scams themselves.
The idea gained momentum after she took a prototype to a hackathon in Germany, where it won first place. Guardian Labs subsequently developed the concept into Guardião, working with Portuguese institutions and research partners. The company says the project has grown from a hackathon prototype into a startup supported by institutional and private partners.
Blocking Scams Before They Arrive
Guardião is designed to analyse potentially fraudulent interactions before they become visible to the recipient.
For calls, the system can analyse conversations in real time, check information against its scam intelligence database and identify manipulation tactics such as artificial urgency, emotional pressure and attempts to obtain sensitive financial information.
For messages, Guardião analyses SMS content before a normal notification is generated. It looks for indicators including spoofing, malicious links and known scam patterns.
If the system determines that an interaction is fraudulent, it can block the call or intercept the message. The user can then receive an alert explaining that an attempted scam was detected, rather than being exposed directly to the suspicious communication.
Privacy Built Into the Technology
A central part of Guardian Labs’ approach is keeping sensitive communications on the device.
The company’s AI runs locally on the smartphone, meaning calls are not sent to remote servers for analysis. Guardian Labs says only metadata is recorded, supporting its privacy focused approach and compliance with Europe’s GDPR framework. (Guardian Labs)
The company also provides a family dashboard that allows relatives to see information such as the number of threats blocked and manage trusted contacts without accessing the user’s conversations.
The goal is protection rather than surveillance.
Learning From Local Scam Patterns
Guardian Labs is building its intelligence around the fact that fraud tactics vary between countries.
The company uses scam reports and intelligence to identify patterns, while its collaboration with Portugal’s Public Security Police has helped strengthen its understanding of fraudulent campaigns.
Guardião’s system is designed to detect not only suspicious words or links but also behavioural patterns associated with manipulation.
That includes attempts to create panic, isolate victims from others or pressure them into making rapid decisions.
Expanding Beyond Consumers
Guardian Labs is also developing an intelligence platform for organisations including banks, telecommunications companies and law enforcement agencies.
The system can help identify active scam campaigns and potentially flag mule accounts used to receive or move money obtained through fraud.
The startup is working toward international partnerships with banks and telecommunications companies, while its consumer product is intended to remain accessible to individuals.
Building a Wider Anti Fraud Network
Guardian Labs says Guardião’s mission is to make digital safety proactive rather than reactive. The company has also launched a WhatsApp channel providing short alerts about scams circulating in Portugal, allowing users to share warnings with family members.
With its technology operating directly on smartphones, the company sees potential for future integration with major communication and social platforms.
What began with one family’s experience has therefore evolved into a broader ambition: building an invisible layer of AI protection that can stop fraudulent communication before it reaches the person being targeted.