Lumo review
A privacy-oriented assistant for cited web search, document work, and encrypted Projects.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Lumo is Proton’s AI chat assistant for people who want to ask questions, write, code, summarize documents, search the web, or generate and edit images. It is available on web, iOS, and Android, with features that also suit people organizing ongoing work or personal material. Its privacy-oriented approach is central: chats, files, and instructions can be organized in encrypted Projects, while Ghost mode supports temporary conversations. Proton also offers a business version with team-oriented administration and privacy features for organizations handling confidential information.
The feature set spans more than conversational answers. Lumo can search the live web with cited sources, accept file uploads for document analysis, and generate or edit images. Custom Lumos allow users to create assistants, while Projects gather chats, files, and instructions. Proton Drive is the only listed integration, so the fit is strongest for people already keeping relevant files there; buyers seeking a broad third-party app ecosystem may prefer another assistant. Listed compliance includes GDPR, HIPAA, ISO 27001, and SOC 2.
The Free plan costs $0 per month and includes limited Max model usage, messages and chat history, and image generations, plus one Project. Lumo AI Plus adds more Max usage, messages and history, and image generations, as well as unlimited Projects and Custom Lumos. According to Proton’s pricing information, Plus has a 30-day money-back guarantee, but its price is not stated clearly enough to compare here. Choose Lumo if encrypted organization, web citations, and Proton Drive matter more than broad integrations; look elsewhere if you need a wide integration set or a clearly specified paid price before deciding.
Lumo pros and cons
- Where it wins
- Searches the web and cites sources in answers
- Analyzes uploaded documents and generates or edits images
- Encrypted Projects, Ghost mode, and Proton Drive integration
- Where it doesn't
- Only Proton Drive is listed as an integration
- Free access limits Max usage, messages, history, and image generations
- The paid plan's price is not clearly stated
Lumo fact sheet, pricing and score →
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