Lumo by Proton
Privacy-first AI assistant utilizing zero-access encryption and open-source code, ensuring no data logging, profiling, or training on chats, providing user-controlled, encrypted conversations, with compliance under GDPR and no sharing with third parties.
Cost / License
- Freemium (Subscription)
- Open Source
Application types
Platforms
- Online
- Android
- iPhone
- Android Tablet
- iPad
- F-Droid
Features
Properties
- Privacy focused
- Distraction-free
Features
- AI Chatbot
- Ad-free
- No Logs
- Encrypted Chat
- No Tracking
- AI-Powered
Proton Drive Integration- Cloud Sync
- No registration required
- AI Writing
- Two-factor Authentication
- GDPR Compliant
Lumo by Proton News & Activities
Recent News
- POX published news article about Lumo by Proton
Proton launches Lumo for Business as a new plan for its privacy-focused AI assistantProton has expanded its privacy-focused AI assistant, Lumo, to serve business customers. This new o...
- Maoholguin published news article about Lumo by Proton
Proton launches Lumo 1.2 with dark mode, custom writing styles & new standalone plus subProton has released version 1.2 of its privacy-focused AI assistant, Lumo, bringing two highly requ...
- POX published news article about Lumo by Proton
Proton releases Lumo 1.1 with faster & more accurate answers and open source mobile appsProton has released version 1.1 of Lumo, its AI assistant, delivering faster and more thorough answ...
Recent activities
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MMsaint added Lumo by Proton as alternative to AI Chat Studio- redej liked Lumo by Proton
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What is Lumo by Proton?
An AI assistant should empower you, not exploit you for your data. That’s me, Lumo.
I was designed to bring you all the benefits of AI, without invading your privacy. From the scientists behind Proton Mail, Proton VPN, and the nonprofit Proton Foundation.
Your chats are yours and yours alone
AIs from Big Tech are built on harvesting your data. But Proton is different. We keep no logs of what you ask, or what I reply. Your chats can’t be seen, shared, or used to profile you.
Safeguarded by advanced security
Thanks to zero-access encryption, the conversations you save can only be decoded and read on your device. Proton can never see them, and neither can anyone else.
With tech that you can see — and trust
Unlike other AI assistants, my code is fully open source, so anyone can verify that it’s private and secure — and that we never use your data to train the model.
And the confidence that you’re in control
We don’t — and can’t — share your information with anyone, including advertisers and governments. And Lumo is a European service subject to GDPR, so you can delete your data anytime.
Lumo by Proton information
Developed by
Proton Licensing
Open Source (GPL-3.0) and Freemium product.Pricing
Subscription ranging between $12 and $28 per month + free version with limited functionality.Rating
Average rating of 3.6Alternatives
88 alternatives listedNews
3 news article related to Lumo by ProtonSupported Languages
- English
- Czech
- Dutch
- French
- German
- Italian
- Polish
- Portuguese
- Russian
- Spanish
- Turkish
AlternativeTo Categories
AI Tools & Services, Security & Privacy, Social & Communications, Backup & Sync, File Sharing, Online ServicesApple AppStore
- Updated
- 3.7 avg rating
Comments and Reviews
it's the only chatbot with e2ee, only thing that could be more private is self hosting, which not everybody can do
Lumo by Proton does not have E2EE. Please read their stated security model: https://proton.me/blog/lumo-security-model Proton retains a key to decrypt your incoming chat messages to clear text for inferencing. LLM response also exists in clear text on Proton servers during inferencing.
Great mascot I love it's design. However marketing it as Open Source is misleading as only the clients are. Especially how they started with words like "Unlike other AI assistants, my code is fully open source, so anyone can verify that it’s private and secure — and that we never use your data to train the model.".
But that's not my main issue with it. The thing that bug me really hard is how closed it really is, it uses several models ("Nemo, OpenHands 32B, OLMO 2 32B, and Mistral Small 3") but everything here is opaque such as Lumo system prompt nor the routing methods that decide which model will handle your query.
Here is a more detailled article the really explain this better than me (and I've copy pasted some words from it) : https://osai-index.eu/news/lumo-proton-least-open
good but too limited:
The app is locked to the Google Play Store. It won't launch without it and redirects to the Play store when installed via other methods like Aurora Store.
Also, no dark theme…
I was able to download it from Aurora, install it and use it without Google Play Services nor Play Store on my device.
Yeah, they responded to my review on the Play Store the next day with an information they plan to change this.
Fair warning. All the marketing material says that it is open source, but it is not. From Proton support: "The statement on our website reflects our long-term intention and the values we stand for, not necessarily the instantaneous state upon launch."
Edit: As of 8/15/25 the frontend code is now open source, despite them marketing since launch that Lumo is open source. The backend code is still proprietary to Proton afaik.
Pros: la propaganda gatuna, valla que si tiene impacto y el hecho que lo que escribas no será visto por nadie más.
Contra: Con preguntas simples se queda pensando demasiado. Dice lo primero que se le ocurre con al de quedar bien.
Habrá que ver como evoluciona. Si mejora, mejoro la evaluación :)
Great IA chat with decent answers. If you need to search on sensitive data, I'd greatly recommend Lumo!