Lumo by Proton

Lumo by Proton

Proton AG·3.8 ★·FREE
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Screenshots

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Description

"Lumo is a zero-access encrypted AI assistant that keeps every conversation private. Your data is never logged, shared, or used to train models. Your chats are yours, and yours alone.

Built by Proton, the privacy brand trusted by over 100 million people and the team behind Proton Mail, VPN, Drive, and Pass.

THOUGHTFUL HELP FOR ANY TASK
Lumo handles everything from quick questions to more complex work. Choose Fast for quick answers or Thinking for multi-step reasoning.

FAST, POWERFUL WEB SEARCH
Get precise, real-time answers in seconds. Lumo cites live sources so you can verify facts, dig deeper, and stay current on news, events, financial data, and more.

CREATE AND REFINE IMAGES AND FILES
Work with images and documents just by telling Lumo what you need, from generating and editing images to analyzing documents. Connect your Proton Drive account for seamless access to stored files.

AI THAT EVOLVES OVER TIME
Lumo gets better every time you use it. Memory retains context and preferences across sessions, and you can set tones and styles to get the exact Lumo experience you want.

STAY PRODUCTIVE AND ORGANIZED
Projects give you dedicated encrypted spaces for tasks that span multiple chats, files, and instructions, while Custom Lumos let you create assistants tailored for specific tasks. Switch between light and dark modes for a more comfortable experience throughout the day.

GHOST MODE
For conversations where you want maximum privacy, choose Ghost Mode. Chats are instantly deleted once you close them for greater peace of mind.

PRIVACY YOU CAN VERIFY
Lumo is founded on zero-access encryption with no server-side chat logs, and never uses your data for profit or model training. Like all Proton products, Lumo is built and hosted in Europe and is fully open-source.

Lumo helps you stay productive, curious, and informed — without ever compromising your privacy. Start a confidential chat for free today.

For more information, visit our website: https://lumo.proton.me/about
Terms of service: https://lumo.proton.me/legal/terms
Terms of use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Our open-source code base: https://github.com/ProtonLumo/ios-lumo"

Developer

Proton AG

Developer ID: 7672479706558526647

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Ratings & Reviews

3.8

2,984 ratings

100,000+ downloads

5★
48%
4★
15%
3★
16%
2★
7%
1★
14%

Recent Reviews

Mand

v2.1.1-gms

I'd use it if I could wake it with the accessibility shortcut and speak to it without having to scroll-tap-scroll-tap to start it listening. Because this is so onerous and can't be done hands free (or with one (long-) tap rather than half a dozen), I keep going back to Gemini. I'm late onto the AI assistant bandwagon, and really did want to like Lumo because of Proton's privacy standards, as well as th claimed features list.

Developer Response

Sorry to hear that. We've passed on your feedback to the team. That said, what you're referring to Lumo "talking to itself" is simply Lumo's thinking process while working on your query. As for the other issues you've mentioned, please contact us using the "Help and feedback" → "Report a problem" option under the account menu so we can assist you.

7 Aug 2026

15 Sept 2026

Jean Jay Quitayen

v2.1.1-gms

Cant login, always something went wrong.

Developer Response

That doesn’t sound right. Are you receiving any error messages during login? We'd be happy to help, but we need some basic details to work with. Please contact us through the contact form on our website so we can assist you further.

16 Sept 2026

15 Sept 2026

Harish

v2.1.1-gms

Excellent app and does what it says does not share data with anyone unlike gemini and chatgpt

15 Sept 2026

Alepfi (Alepfi5599)

v2.1.0-gms

Sounds secure and does a decent enough job at a variety of tasks. I think the limit of chats only being visible for seven days is a little strict, especially since I am already a proton subscriber (just not for Lumo). Also, the sign in buttons don't do anything, I cannot sign in in the app, only in the browser version. response: The button does not react to pressing it. downloaded from playstore.

Developer Response

Thank you for the review. We've taken note of your feedback. As for the login issue, could you share more details? Is the button completely unresponsive? Are you receiving any errors by chance? Where did you download the app from exactly? Contact us through the contact form on our website so we can help.

15 Sept 2026

15 Sept 2026

Chazda 3rd

v2.1.1-gms

uninstalled same hour. Needs lotsa work. I reinstalled and the same stupid message appeared immediately in my first inquiry: .."reached your Lumo 2.0 Max limit Sign up for free to continue chatting and unlock access to chat history, starred chats, and more features." Nice welcome, eh? How could I have reached my limit on the very first inquiry? dahhh Done with this.

Developer Response

We're sorry to see that you're dissatisfied. If you're experiencing any issues using Lumo, or if you have any suggestions on how we can improve the app, feel free to let us know through the "Help and feedback" option under the account menu. We'd be happy to have your feedback.

14 Sept 2026

15 Sept 2026

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