Lumo: The AI assistant that won’t spy on you

In an era where most artificial intelligence assistants quietly collect every word you type, a new entrant is taking a very different path. Lumo, launched by Proton, promises conversations that are as private as a whispered secret.

It does not log your chats, deploys end-to-end encryption for everything, and it refuses to sell your data to advertisers. In other words, it is an AI assistant that works for you, not the other way around.

Proton is no stranger to privacy. Known for Proton Mail, its encrypted email service, and other secure tools, the company has built a reputation as a guardian of online confidentiality. Now it has stepped into the competitive AI space with the same ethos.

Lumo runs on open-source models hosted in Proton's European data centres, away from the data-hungry eyes of US and Chinese tech giants. Your queries never leave Europe, and no third party ever gets access.

From the moment you open Lumo, you can feel the difference. You do not even need an account to start chatting. Without logging in, you can ask up to 25 questions a week. Sign in with a free Proton account, and the limit rises to 100, with your encrypted chat history synced across devices. For those who want more, Lumo Plus offers unlimited chats and larger file uploads for a monthly fee.

The privacy measures go far beyond marketing claims. Conversations are stored using Proton's "zero-access" encryption, meaning even Proton cannot read them. Ghost Mode deletes a chat the instant you close it. Uploaded files are never saved, whether they are stored locally or in Proton Drive. Web search is disabled by default, and when switched on, it uses privacy-friendly search engines.

In practice, Lumo feels like a cross between a knowledgeable assistant and a loyal confidant. Just like other AI chatbots, it can summarise documents, generate code, rewrite emails, or analyse uploaded files without keeping a trace.

The privacy measures go far beyond marketing claims. Conversations are stored using Proton's "zero-access" encryption, meaning even Proton cannot read them. Ghost Mode deletes a chat the instant you close it. Uploaded files are never saved, whether they are stored locally or in Proton Drive.

In tests, it handled tasks like producing a synopsis of Dostoevsky's Crime and Punishment and drafting software specifications for a Rust-based desktop client. While smaller than some commercial rivals, it delivered answers quickly and with surprising accuracy.

Lumo also integrates seamlessly with Proton's ecosystem. Files from Proton Drive can be dropped straight into chats for analysis. Looking ahead, the company hints at deeper ties — drafting emails in Proton Mail, creating event summaries in Proton Calendar, or assisting in future Proton Docs.

Of course, it is not without limitations. Lumo cannot fetch information from arbitrary web links, and large documents can slow processing. Yet these trade-offs are a consequence of keeping operations within a tightly controlled, privacy-focused framework.

Proton is positioning Lumo not just as a product, but as part of a larger European push for technological independence. The company is investing over €100 million into EU infrastructure, partly in response to potential Swiss surveillance laws. Lumo will be the first Proton product to shift entirely into the EU, reinforcing its commitment to privacy-friendly jurisdictions.

In a world where most AI assistants are built to learn from you — and profit from what they learn — Lumo takes the opposite approach. It learns nothing about you, remembers only what you choose, and erases the rest. For those who value privacy as much as productivity, that is a refreshing change.

You can try Lumo for free on the web or via its Android and iOS apps. No account is required, no logs are kept; in today's AI landscape, that alone makes it remarkable.