Preamble is a professional, high-performance LaTeX editor built specifically for Android. It allows you to write, edit, and compile complex scientific papers, academic theses, and mathematical documents directly on your device using a native Rust port of the Tectonic typesetting engine. By bringing compilation directly onto your hardware, Preamble eliminates the need for remote cloud rendering servers, slow online queues, or expensive monthly subscriptions.

Whether you are a researcher, academic, university student, or hobbyist writer, Preamble provides a powerful workspace to draft your LaTeX documents on the go, even when completely offline.

Key features:
- True local compilation: Features a native, lightning-fast compilation engine based on Tectonic (a modern XeTeX-based engine). Compilation runs directly on your device's CPU, keeping your private documents completely local.
- Intelligent package caching: An internet connection is only required when your project requests a package or dependency (`.sty` or `.cls` files) for the first time. The app automatically fetches the package from the CTAN repository and caches it locally. Subsequent compilations require zero internet access.
- Professional code editor: Engineered for long writing sessions with standard syntax highlighting, regex-based tokenization, and edge-to-edge layouts that maximize your workspace.
- Native PDF viewer: Instantly preview your compiled PDF documents using a high-performance built-in viewer. Supports fluid multi-axis panning, pinch-to-zoom gestures, and fast page navigation without any lag.
- Adaptive IDE layouts*: Designed to scale beautifully across all Android form factors. Enjoy a streamlined layout on mobile phones, a two-pane list-detail layout on tablets, or a full-featured multi-pane desktop IDE when using Samsung DeX, Chrome OS or any other desktop environment.
- Privacy & security first: Preamble is built on Android's modern Scoped Storage model. Your files reside securely within the application's local sandbox, requiring no intrusive permissions to access your external storage. Your document contents never leave your device.
- Robust file manager: Organize your projects and document hierarchies with a clean, native file explorer. Easily create, rename, organize, and delete files or folders. Export your final PDFs seamlessly to Google Drive, Downloads, or local folders.

How does it work?
1. Set up a new project or create folder structures for images, bibliographies, and source files.
2. Write LaTeX code using our optimized editor.
3. Press the compile FAB. If it is the first time compiling a particular package, Preamble will download it. Otherwise, it compiles instantly using your offline cache.
4. Review the output PDF and export it using Android's system file sharing interface.

* still in development.