Lumo by Proton

This app is simply spewing Wikipedia talking points.

During my very first use of this app immediately upon installing, it became apparent that reading responses would be nigh impossible. Why? Because while the keyboard disappeared upon sending my request, the space it took failed to collapse, reducing the space available to display the response to a mere 6 lines of text. Additionally, a button overlayed the response text. Its purpose seems to be to scroll down to the end of the response. Unfortunately it made it impossible to reach the text displayed next to it, for the purpose of scrolling. So the only area that would respond to scrolling exists above that button-a mere three (3) lines of text. Imagine having to scroll through several paragraphs of a response when you can see only 6 lines at a time, and can use but 3 of them to scroll through the remainder. An utter usability disaster, this app does not lend itself to be used for anything serious, it its current state.

I love the idea behind the app, however when tables are generated I can’t see the entire table, I can see 2-3 columns top and I can’t horizontally scroll, which makes lumo unusable in my phone

5 Nov 2025 Edit After the iOS 26.1 update and the last Lumo update, the below problem is resolved. Note: The GPT4.0 still gives fake data and fake references. But that's everywhere. Updated stars from 2 to 4. ----- Original: iPhone 13, upgraded to iOS 3-4 days ago. All apps in app store updated as of 09:00 (GMT -4). After asking a question, keyboard can be "dismissed" but the UI never readjusts, so Lumo and all its windows/panels take up just 1/3 of the phone, leaving a blank 2/3 "white space". The entire conversation has to occur in a 2" box with a 2-line reading window. I've tried logging out/in and reinstalling. "Help/Settings" also becomes totally unresponsive. Will edit stars and review when fixed. As for the LLM, it's workable on my regular Pro sub for the few questions as I am a heavy Proton user but not a heavy AI / LLM user. I do not find it worth an additional subscription and would simply use another product if locked out of Lumo on a paid Pro (non-AI sub) basis.

-=Update 11/5/25=- I bought the Lumo+ and it worked, but missing features I listed in my first review. But since the last update, Lumo+ no longer works with the app at all. Customer service rep Laze was horrible and did not address any of the issues. Since I was no longer receiving the product I paid for only 60 days after I purchased the Lumo+ subscription, I kindly asked for a refund of unused service until they fix all the issues. Laze did not do this or send it up to a higher level as requested. I’ve been a paying Proton Unlimited customer for many years and I am disappointed by Protons terrible Lumo app product and even worse customer service. —— There is no way to adjust the text size in the app. The app does not save your history or favorite inquiries and deletes everything when the app closes. It also does not save anything to your Proton drive if you try to do this through a web browser. I have Lumo+.

I haven’t actually used it much yet, so I don’t necessarily wanna give a star score but the links to the privacy policy and terms of service don’t work along with a bunch of other links.

I loved the app but I’m getting a “unsupported browser” error now…

Update: My initial review was pretty harsh, but Lumo really was playing it too safe to be useful. Lately it is pretty good for creative tasks even if somewhat sensitive topics are involved. The safeguards on this are extremely strict, to an extent where even harmless inquiries result in the “can’t help with that” response. I understand the desire to prevent LLMs from being misused, but the current state of Lumo is absurd. Is it because of the EU being a pathetic joke that brings shame to the concept of a democratic society? What’s next, will I need to provide my digital ID to use my “confidential” AI assistant? What a joke.

UPDATE: Proton launched features as promised and directly addressed 2 of my 5 issues. Images are on the roadmap as well. Proton Doc files say they’re coming soon. That just leaves the hallucination problem, which is still prevalent. That being said, Lumo now fulfills most of my needs and, as promised in my original review, I have switched to Lumo Plus. Review changed to 4 stars. Will update again when images are added and/or when hallucinations are addressed. Thoroughly impressed with Proton’s work here! My issues with Lumo are exclusively feature parity. I use ChatGPT quite heavily, and am looking for an alternative option due to recent updates to it. I don’t expect an exact 1:1, but there are some things that, if included, would cause me to swap over to Lumo as my primary assistant: 1. Dark mode. Please. 2. The ability to attach Proton Docs. I already subscribe to Proton Unlimited and heavily use Proton Drive. This would make the ecosystem far more usable. 3. Image file types as supported file types for uploads. I frequently screenshot things and ask ChatGPT about it. I’d love to do that with Lumo. 4. Switches, toggles, customization. I’d love to be able to give Lumo custom instructions without having to upload a document for every chat with instructions written in it. 5. Hallucinations. Sometimes they’re charming, but they’re often not. Reduced hallucinations would be a big plus. With all that said, Lumo has started in an excellent place. Proton seems to be doing a great job with frequent enough updates and I’ll be watching this closely. And privacy focus on top of that? Chef’s kiss. If this gets to the point where it can cover most of my daily use cases, I’m switching to it immediately.

Nice AI assistant! I wish you can be clearer about the daily limits, chat history limits. Also it would be great if we can rename each individual chat. That way, finding the right conversation would be quick and easy. Thank you