Lumo by Proton

In-app purchases
3.5
2.13K reviews
Content rating
Everyone
100K+
Downloads
Content rating
Everyone
Learn more
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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
Apr 24, 2026

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

3.5
2.02K reviews
Vince E
September 8, 2025
Generally seems pretty good, and it appears that the team is making quick improvements. However the weekly prompt limit on the free tier isn't very generous. It would be great if there were additional tiers for existing proton subscribers to further try it, before adding another subscription... especially with other free semi-private options like duck.ai that don't appear to impose any limits.
37 people found this review helpful
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Proton AG
September 9, 2025
Thank you for your review. We've shared your feedback with the team accordingly.
Nayeem
April 27, 2026
What ya'll doing, devs? Please fix the bugs for the android users. Don't ask me the issues I am facing. Just use it on an android phone. The responses stop suddenly, and most of the time, it doesn't respond at all. Shows red error saying, "Cannot show properties of undefined (reading 'name')", and the little retry button doesn't work either. Please, yo devs, fix it! It will be much appreciated.
10 people found this review helpful
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Proton AG
February 20, 2026
Thank you for your review. We've made sure to document your feedback accordingly. You can follow our blog (https://proton.me/blog) and our direct channels for any news and updates related to Lumo. On another note, if we can help with any issues, please feel free to contact us at https://proton.me/support/contact?topic=lumo at any time.
Henry James
April 9, 2026
Great privacy respecting ai app. Saw a lot of people hating on it in the reviews so I thought id drop a positive review. One of the few ais I could find that doesnt sell off all your data, absolute godsend. A little slower than other ais but that's to be expected with protons much lesser resources than open ai and whatnot
8 people found this review helpful
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What’s new

Whisked in a handy home screen widget so you can pounce on conversations instantly, plus a sleek native composer that makes crafting your messages as smooth as a cat nap in the sun.