Lumo by Proton

In-app purchases
3.9
1.08K reviews
50K+
Downloads
Content rating
PEGI 3
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image

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
Sep 17, 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

3.9
1.03K reviews
Simon Carter
August 28, 2025
Fast and knowledgeable, I've been using Lumo as a way to learn about the background, social and political to The Battle of Hastings. I've been able to get excellent, detailed and clear English responses to all my questions and musings around this historical period. Really easy to use in its text-based form. I've not had a chance to try anything else yet. So far, so good. 4-stars and it could be 5-stars but I need to use it for a while. Impressive, frankly.
21 people found this review helpful
Did you find this helpful?
Proton AG
August 29, 2025
Thank you for your support. We'd love to earn a 5-star rating from you -- if you have any suggestions on how we can improve our service, don't hesitate to pass your feedback along to us at https://proton.me/support/contact. We always appreciate our community's input.
loiemarie
October 5, 2025
This may be the worst app experience I've ever had. I've been a Proton user for over 8 years. I really wanted this app. Voice to text does NOT work. They will gaslight you and tell you it's you. Voice to text works on ALL other apps on my phone, permission has been given to Lumo. They will spend the day with you having you do "fixes". They are not fixes because none of it was "broken" on my end. I uninstalled and reinstalled the app. I've cycled through their instructions multiple times.
1 person found this review helpful
Did you find this helpful?
Proton AG
October 6, 2025
Sorry to hear that. Can you clarify the issue further? What is the exact behavior you're experiencing with the voice input option, and which specific steps are you taking that lead to the issue? Contact us at https://proton.me/support/contact so we can investigate, or share your ticket number with us here if you've already reached out to our team.
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.
47 people found this review helpful
Did you find this helpful?
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.

What’s new

🐾 Squished payment screens back into shape - no more getting stuck on tiny screens like a cat in a too-small box
🐾 Fixed those pesky GrapheneOS debug errors that were making us hiss and swipe at the screen
🐾 Composer now stays put instead of wandering around like a curious kitty - much more stable positioning
🐾 Caught and fixed multiple small bugs (literally, we're cats - it's what we do) šŸ›āž”ļøšŸ˜ø