Lumo by Proton

In-app purchases
3.7
575 reviews
10K+
Downloads
Content rating
Everyone
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About this app

Ask anything. It’s confidential.

Meet Lumo, the privacy-first AI assistant created by Proton, the team behind encrypted email, VPN, password manager, and cloud storage trusted by over 100 million people.

Lumo helps you stay productive, curious, and informed — without ever compromising your privacy.

Start a confidential chat today.
Updated on
Jul 28, 2025

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
No data shared with third parties
Learn more about how developers declare sharing
This app may collect these data types
Personal info, App activity and App info and performance
Data is encrypted in transit
You can request that data be deleted

Ratings and reviews

3.7
543 reviews
J C
August 17, 2025
extremely fast. highly knowledgeable. medium strength context when it writes back. so it's not short. it's not long. it's medium. which is nice because I find shot GPT to be extremely short actually. Even with a deep research bot. happier with this than Chat GPT. proton came a long way. well it's never been bad or anything but tons of additional features now in their suite of toys. I just hope they're a fan of the light.
1 person found this review helpful
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Amirsattar Banaee
August 18, 2025
still has a lot of catching up to do. things like web search and deep thinking, in addition to some basic quality of life features like pressing the enter sending the text instead of starting a new paragraph or a dark mode. but it does what it's trying to do, keeping you safe. it's the only one that doesn't require login and has a private mode. edit: ok it seems to have a web search but it's bugged and doesn't work most of the time.
5 people found this review helpful
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Proton AG
August 18, 2025
Thank you for your review. We've shared your feedback with the team for future consideration. You can follow our blog (https://proton.me/blog) and our direct channels for any news and updates. As for the issue you're experiencing with the web search function, contact us at https://proton.me/support/contact so we can investigate it further.
Francesco Varrato
August 14, 2025
I seriously tried to like it. I even paid for the year, to support it. I'm so disappointed. Often, when opening the app (or even on the browser) it takes a couple of attempts to just get started. When working, it doesn't provide the sources of its responses. I cannot share images to it to analyse. In its current implementation it's just a sort of verbose search engine. I seriously hope it gets better, soon.
11 people found this review helpful
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Proton AG
August 18, 2025
Sorry to hear that. We've shared your feedback with the team for future improvement. As for the sources, they are indeed provided when using the web search function.