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OpenNotas
OpenNotas is an open-source, encrypted note-taking PWA replacing Apple Notes and Google Keep with client-side AES security and custom cloud storage sync.
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Overview
Software engineer Tong Xuan Hoai built OpenNotas after replacing a broken iPhone with an Android phone and losing access to his Apple Notes library. Frustrated by the lack of markdown formatting and cross-platform syncing in default mobile apps, he assembled a Progressive Web App that runs identically across desktop and mobile browsers. Today, that origin gives OpenNotas its straightforward capture-and-close focus, avoiding complicated workspace setups in favor of rapid, encrypted text entry.
Why OpenNotas instead of Obsidian
Obsidian relies on a local vault of Markdown files and requires paid Obsidian Sync or third-party tools to move notes between a computer and a phone. For everyday writers, configuring mobile synchronization or troubleshooting folder conflicts turns note-taking into a maintenance chore. OpenNotas bypasses the file-system hurdle by running as a web app that stores notes in local browser memory and connects to remote storage through pluggable adapters.
Instead of locking users into a proprietary cloud or requiring manual vault backups, OpenNotas integrates with independent services like Turso for note text and S3-compatible object storage for embedded pictures. Notes receive client-side AES encryption before leaving the browser, ensuring cloud providers cannot read personal records. While Obsidian offers graph views, canvases, and community plugins, OpenNotas matches the simpler need: a zero-cost, encrypted notebook that syncs across phones and laptops with minimal setup.
What it does well
- Runs in any modern browser as an installable Progressive Web App, providing an application-like experience without app store downloads.
- Encrypts note text on the device using AES before transmission, keeping private thoughts hidden from storage providers.
- Connects to external storage adapters such as Turso LibSQL for notes and S3-compatible buckets for images, preventing vendor lock-in.
- Supports offline writing through local browser storage, automatically caching changes until a network connection returns.
- Provides multiple Markdown editing engines, allowing writers to switch between live-preview formatting with Milkdown and raw Markdown via CodeMirror.
- Exports complete note archives directly to local disk, giving readers full ownership of their data without proprietary export formats.
