Lumo by Proton

Lumo by Proton

Proton AG·3.7 ★·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

3.7

3,176 ratings

100,000+ downloads

5★
67%
4★
0%
3★
0%
2★
0%
1★
33%

Recent Reviews

Deborah Smitten

v2.1.4-gms

Asked it to make me a schedule for a study day. It didn't check the format of my calendar app (which I'd given it). Couldn't create an ics file for upload. Repeatedly gave option of just typing in the day's schedule when I'd asked for a file to upload. Turned a 2 min job into 30. Gave me a made up email address for me to complain to. Doesn't integrate with the other basic Proton email, calendar and drive apps. Pretty much useless currently.

11 Oct 2026

Shinku And Lacrimosa

v2.1.4-gms

The best ai on the planet.

11 Oct 2026

Call Me Dave

could you guys make this Ai advance thinking cus it always gives wrong image generated whenever I requesting. Make it more like ChatGPT with advance thinking kinda like that, that's all.

11 Oct 2026

Michael C

v2.1.4-gms

as far as llms go if you have to use one grudgingly this is a decent option competing with things like duck AI and ecosia. especially if you're already using proton for email or VPN I would probably suggest, however, the browser version create a shortcut free URL or web app. the less permission heavy, mostly equal on features. some aesthetic benefit to the app. notifications might be better. but I don't need notifications for an llm. interesting competition with duck ai and ecosia

Developer Response

Thank you for the review. If you have any particular suggestions on what we could further improve to reach a 5-star rating, feel free to let us know through the "Help and feedback" option under the account menu. We always appreciate our community's input.

9 Oct 2026

9 Oct 2026

Kazuma Shibasaki

v2.1.4-gms

would be nice to have an auto mode for selection of ai models and answer mode. also support landscape mode.

Developer Response

Thank you for the review. We've shared your feedback with the team for future improvement. You can follow our blog and socials for any news and updates.

9 Oct 2026

9 Oct 2026

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