Proton, the Swiss company known for its encrypted services like Proton Mail and Proton Drive, has launched Lumo, an AI assistant built with privacy as its primary focus.
Highlights
- Privacy-First by Design: Lumo offers end-to-end encryption, zero chat logging, and an optional “ghost mode” that deletes conversations after session end.
- Account-Free Access: Anyone can use Lumo without a Proton account, with support for uploading and querying documents instantly.
- Cross-Platform Availability: Lumo is accessible via web and mobile apps for iOS and Android, ensuring broad user reach.
- Built on Open-Source Models: Powered by Mistral’s Nemo and NVIDIA’s OpenHands 32B, all inference is handled within Proton’s European data centers—fully GDPR-compliant.
- Secure File Interactions: Proton Drive subscribers can link cloud storage for encrypted file analysis and AI-supported search.
- No Data Used for Training: Proton guarantees that user inputs are never used to fine-tune or improve AI models.
- Strict Web Search Controls: Web access is off by default. When enabled, it uses privacy-respecting engines to reduce tracking exposure.
- Flexible Pricing: Free tier available; Lumo Plus ($12.99/month) adds encrypted chat history, bulk uploads, and unlimited usage.
- Part of Proton’s “EuroStack” Vision: Lumo anchors a €100M initiative to build a sovereign, privacy-driven tech stack in Europe.
In contrast to many mainstream AI platforms, Lumo is designed to protect user data by avoiding chat logging, supporting end-to-end encryption, and offering a “ghost mode” that deletes conversations immediately after closure.
Core Features and Accessibility
Lumo is available across platforms via web clients and mobile apps on both iOS and Android. Importantly, users don’t need a Proton account to access the chatbot.
Anyone can upload documents and ask questions about them, and Proton Drive subscribers can link their cloud storage for more advanced file interactions.
Though Lumo includes web access capabilities, it does not prioritize real-time search results. This design choice reflects the platform’s emphasis on minimizing data exposure in favor of preserving user privacy.
Built on Open-Source Models and European Infrastructure
Lumo is powered entirely by open-source language models, including options like Mistral’s Nemo and NVIDIA’s OpenHands 32B.
All data processing takes place within Proton’s European data centers—ensuring compliance with GDPR and avoiding potential jurisdictional concerns associated with U.S. or Chinese cloud services.
Proton has emphasized that user data is never used to train these models. This aligns with the company’s long-standing commitment to privacy and transparency across its suite of tools.
End-to-End Encryption and No Data Retention
Lumo implements zero-access encryption, which ensures that only users can decrypt their stored conversations. Even Proton cannot access this data unless it’s explicitly decrypted on the user’s device.
The assistant offers a ghost mode that allows for temporary, session-only chats. Once a conversation window is closed, all content is permanently deleted.
Proton also maintains a strict no-logs policy, confirming that neither chat logs nor usage data are retained on its servers or used to improve its models.
Highlights
- No Account Required – Anyone can access Lumo immediately, with no Proton sign-up needed.
- File Support – Users can upload files for document-based queries, with full encryption maintained throughout.
- Privacy by Default – Web search is off by default. When enabled, it routes through privacy-respecting engines.
- Flexible Plans – A free version offers basic access, while Proton subscribers receive encrypted history support. A $12.99/month “Lumo Plus” plan offers unlimited usage and advanced features like bulk file uploads.
A Strategic Move in Europe’s Tech Sovereignty Push
Lumo is a key component of Proton’s broader investment in building a European technology stack focused on privacy and transparency.
As part of its “EuroStack” initiative, Proton is investing over €100 million to create independent, privacy-oriented digital infrastructure. Lumo represents a cornerstone of this effort, positioned as a secure alternative to AI services tied to proprietary ecosystems or cross-border data exposure.
