Proton today launched Lumo, an AI assistant that promises to keep your conversations completely private. Best known for its encrypted Mail and VPN services, the Swiss company says it built Lumo as an alternative to mainstream AI tools that typically capitalize on users' data by using it to train their large language models (LLMs).
Lumo can be used just like other AI chatbots (Open AI's ChatGPT or Google Gemini, for example) so it can do things like analyze documents, rewrite emails, and generate code. Proton says Lumo doesn't keep chat logs on its servers, and everything stays encrypted on your device using the same technology that protects the company's other services, so no one else can read your conversations – including Proton itself.
The service runs on open-source AI models like Mistral's Nemo and Nvidia's OpenHands 32B. The models operate from European data centers that Proton says it controls directly. Users' questions and responses don't get fed back into the system to train future versions, so there's no risk of your private information showing up in someone else's chat.
Lumo includes a "Ghost mode" that makes your current conversation disappear forever when you close it, while the assistant's web search feature (if you turn it on) uses privacy-friendly search engines. You can also link Proton Drive files to Lumo and everything stays encrypted.
Lumo is free to use at Lumo.proton.me and does not require a Proton account when accessed. However, if you have a Proton account, your chat history can be saved using the company's "zero-access" encryption across all your devices. There are also mobile apps for iPhone and Android.
For power users, Lumo Plus costs $12.99 per month and removes limits on chats and file uploads. Announcing the chatbot, Proton CEO Andy Yen said the company built Lumo because AI shouldn't become the world's most powerful surveillance tool. "For this reason, we believe it is essential to provide an alternative that protects privacy and serves users as opposed to exploiting them."
Lumo by Proton is available to download from the App Store. [Direct Link]
