Lumo by Proton

In-app purchases
3.6
2.36K reviews
Content rating
USK: All ages
100K+
Downloads
Content rating
USK: All ages
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
Jun 12, 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

3.6
2.24K reviews
Neil
October 16, 2025
Edit: Lumo has improved a lot, but there are still mistakes, and a high price for what you get. I'm on a duo plan as of now, and hope that there will be adjustments to lumo for paying users. First review: Lots of mistakes, fails to answer, requires additional subscription to protons unlimited plan for unlimited access, very high price compared to what you get.
30 people found this review helpful
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Proton AG
July 27, 2025
You can use the thumbs down button under the response to share your input with us about any inadequate responses. Our team is looking into these reports for future improvement. On another note, adding Lumo would require raising the price of Unlimited due to the cost of AI, so our current plan is to keep Lumo standalone rather than raising prices.
B G
May 22, 2026
I appreciate the design and it has some clever uses but it has been riddled with issues for me making it a non usable product. A 3rd of the time messages populate with nothing in them. Half the time I submit something it tells me to retry later because of system issues. It doesn't let me resubmit and I have to force close to try again. Sometimes it can process attachments, most of the time it can't.
5 people found this review helpful
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Proton AG
May 26, 2026
Sorry to hear that. Are you experiencing these issues with specific prompts? If so, would you mind sharing them with us? Are you using the free version of Lumo, or are you on a paid plan? What type of attachments have you experienced problems with? Please contact us through the contact form on our website with more details so we can help.
Bryce Cable
May 19, 2026
App works great for me, supports voice input and files (had some problems with this though). Responds quickly usually. For the platform iself, limited weekly input is kind of insane, especially since I'm already an unlimited member. I didnt even use it that much and got locked after a day. Need to pay another monthly fee to use normally
3 people found this review helpful
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Proton AG
May 19, 2026
Thank you for your review. We're currently keeping Lumo as a standalone product to avoid increasing the price of our Unlimited plan. This way, we can keep the cost manageable for all our users while still offering advanced AI features to those who want them. That said, if you're having any issues, contact us through the contact form on our website.

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.