LetX.app Reviews and Details

Questions & Answers

1. Why should a person choose LetX.app over its competitors?

   Overleaf charges as you add collaborators and gates version history behind a subscription. LetX gives unlimited collaborators and 15 versions free, with full history at $18/month, or $9/month for students.

   Against the newer AI-native LaTeX editors, the difference is data: those route your unpublished manuscript through third-party models, while LetX keeps it out of training entirely.

   Against desktop editors like TeXstudio or Texmaker, there is nothing to install or maintain, no TeX distribution, no package management, and an identical environment for every co-author.

2. What's the story behind LetX.app?

   LetX started because collaborative LaTeX was either expensive or private in name only. Overleaf's pricing scales with the people you write with, which is backwards for a thesis committee or a five-author paper. Then the AI-native editors arrived with a worse trade: faster tooling in exchange for sending unpublished work to model vendors.

   LetX was built to refuse both unlimited collaborators on every plan, and an explicit ai-train=no declaration. Launched 27 January 2026, it has grown to 1,200+ users across 90+ universities and research labs in 30+ countries, largely by publishing the regional university thesis templates nobody else maintained.

3. What makes LetX.app unique?

   Two things that nothing else in the category combines. Collaboration is genuinely unmetered. Every plan, including the free one, allows unlimited simultaneous collaborators, so cost never scales with the number of co-authors. And LetX declares ai-train=no and is not tied to any LLM vendor, so unpublished research is never used as training data. The template library is also unusually deep for regional needs: 442 templates, including university-specific thesis formats that most editors don't carry.

4. How would you describe the primary audience of LetX.app?

   Researchers, postgraduate students and academic staff writing papers, theses and grant proposals, along with the labs and university departments they work in. Usage concentrates around thesis submission and journal deadlines. A secondary audience is job-seekers and engineers using the CV and résumé templates.

5. Which are the primary technologies used for building LetX.app?

   Go with Gin for the API; React, TypeScript and CodeMirror 6 on the front end; Yjs CRDTs over WebSocket for real-time collaboration; PostgreSQL, Redis and S3 for storage and coordination; and SQS-queued compile workers running a full TeX Live distribution on AWS ECS Fargate.

6. Who are some of the biggest customers of LetX.app?

   LetX is used by individual researchers and students at 90+ universities and research labs in 30+ countries, including INGV Italy, INPE Brazil, CAB CSIC-INTA Spain, UCSD, TUM and Korea University. These are institutions where our users are based rather than institutional accounts.