Proton, the European company known for privacy-focused email, VPN and cloud storage products, has significantly upgraded its AI chatbot Lumo, and the new Lumo 2.0 version is now live. First launched in August 2025, the chatbot has picked up image generation, a slower but smarter Thinking mode, improved web search and better memory recall, closing much of the gap with mainstream tools like ChatGPT and Gemini while keeping its privacy-first pitch intact.
Getting Started With Lumo 2.0 and What It Costs
Lumo is available on the web, on Android and on iOS, and anyone can start using it for free without even needing a Proton account. A paid Pro tier costs $12.99 per month and unlocks a full chat history, access to more advanced AI models, and higher usage limits for both chat volume and file sizes. Unlike Proton's other subscriptions, the Lumo Pro tier is not bundled into existing Proton packages, it has to be purchased separately.
How Proton Handles Privacy
Proton's launch material for Lumo 2.0 puts heavy emphasis on how little data and personal information the assistant retains. Some storage is unavoidable for the chatbot to function, and users who want to can keep their chat history around to refer back to later.
Chats are not used to train the underlying AI models that power Lumo. That is a toggleable option in chatbots such as ChatGPT and Gemini, and it is also one of the selling points behind Apple Intelligence, but many other AI products are far less upfront about whether conversations feed back into training. ChatGPT, for instance, does use conversations to train its models by default, although users can opt out.
Lumo also uses zero-access encryption on chats, meaning nobody, not law enforcement, not government agencies, and not even Proton's own staff, can view what is inside a conversation. That marks a clear point of difference from other AI platforms, even though companies like Google and OpenAI point to strict legal processes and regulation that are meant to keep stored chats private. Still, like every other AI product built on large language models, Lumo cannot offer full end-to-end encryption, a limitation Proton itself acknowledges.
Comparing Lumo's privacy protections against rival services is not entirely straightforward, because so much depends on whether a person is saving or deleting chats as they go. The picture is further complicated by OpenAI currently being required to retain a large portion of user chats, including ones that were deleted, because of an ongoing lawsuit brought by the New York Times.
What is clear is that Proton is treating this issue with more seriousness than most competitors right now. Unlike Gemini, which reviews some user chats by humans in order to, according to Google, help improve its services, Lumo has no such human review process, a reminder that users should be cautious about sharing anything too sensitive with any AI chatbot. Gemini does offer an auto-delete option for chats, but Lumo's approach of skipping human review altogether goes a step further. Lumo also runs on open source AI models, adding a layer of transparency, and Proton has structured the service without third-party partnerships, so its privacy policies and protections cannot be diluted by ties to outside companies. Additional detail on the large language models Lumo uses and how privacy is handled is available on Proton's own website. As with all of Proton's products, Lumo operates out of Europe, which means it is not governed by the same data surveillance and retention rules that apply in places like the United States.
Lumo 2.0 Goes Head to Head With ChatGPT
Earlier impressions of Lumo 1.0 flagged image generation and deep reasoning as two areas where it fell short of rival chatbots. That is no longer true. Lumo 2.0 can both generate and analyze images, a capability that was put to work producing images of a spaceship, a forest cabin and a cartoon cityscape.
The results were closely matched between the two tools. Lumo held its own against ChatGPT overall, and its spaceship image came out particularly strong, arguably the best of the three. ChatGPT's images tended to look slightly more striking on the whole, but they also drifted further from the original prompts more often. Lumo lets users refine generated images through follow-up prompts in the same way ChatGPT does, and it produced usable images noticeably faster, though the trade-off was that its output came in at slightly lower resolutions than ChatGPT's.
Lumo 2.0 also introduces a new Thinking mode, which runs slower than the standard Fast mode but delivers stronger reasoning. Applied to several dense scientific research papers, its analysis and summaries came out roughly on par with ChatGPT's in terms of quality of writing and structure, and on a couple of occasions Lumo actually explained the material in a more accessible way than ChatGPT did.
Web search is another area that has moved forward in Lumo 2.0. It now matches ChatGPT's ability to gather and organize information pulled from the web. Both chatbots were used to summarize a handful of current tech news stories, and both handled the task equally well, showing live updates on search progress and listing references at the end. ChatGPT's summaries tended to run more thorough, but Lumo's presentation of the same information came across as cleaner.
More Upgrades and Where Lumo Stands Now
Beyond images, reasoning and search, Lumo 2.0 also brings improved memory recall and management, plus a new Custom Lumos feature that mirrors Custom GPTs on ChatGPT. It lets users build siloed AI assistants tuned for specific jobs, such as polishing written text or returning web search results in a particular format.
Taken together, these additions show how far Lumo has come since its original release, both in the quality of its answers and in the breadth of features on offer. ChatGPT remains the more mature product overall, still ahead on things like live voice mode and dedicated coding assistants for professional developers. But the gap between Lumo and the established AI chatbots has narrowed considerably, especially for everyday, casual use, making Lumo worth a look for anyone who wants an AI assistant built around stronger privacy principles.
