A private AI knowledge assistant that learns from your files, notes, and journals — and answers questions about them.
Upload documents, paste notes, or speak aloud — Second Brain indexes everything and uses it to give you grounded, cited answers.
Every question searches your knowledge base first. Answers cite which files they came from so you can verify the source.
Hands-free conversation using Whisper (online), Vosk (offline), or your device's built-in speech engine. Responses are read back aloud.
Ingest PDFs, Word docs, markdown, code, images, CSVs, and more. Files are chunked and embedded for semantic search.
Daily entries with mood tracking and tags. Entries are automatically indexed so you can search and chat about your own history.
Ask for a summary of the last 30 days — recurring themes, mood patterns, and a reflection question generated from your journal entries.
Conversations are saved, searchable, and resumable. The full message thread is restored on reload so context is never lost.
Switch between Anthropic's Claude models for quality and Ollama for full privacy. No vendor lock-in.
The app is designed for quick captures and hands-free use, not just a mobile wrapper.
Attach a photo to any chat message. After the reply you're prompted to save the image to your knowledge base for future reference.
Chat saves are queued locally when offline and synced automatically when the connection returns.
Before sending to a paid model, see the estimated token count and max cost. Confirm or cancel before anything is sent.
If the app is in the background when a response finishes, a notification appears so you don't have to wait with the screen on.
Narrow the context to specific files or topics before chatting. Useful when you want answers only from a particular document.
Correct a misheard transcription and the original audio is saved as a training pair for future Whisper fine-tuning.
This is a debug build not distributed through the Play Store. Follow these steps to install it.
Tap the Download button, sign in with your Second Brain credentials, then save the APK to your device.
In Settings → Security (or Apps), allow installs from your browser or file manager.
Tap the downloaded APK in your notifications or file manager and follow the install prompt.
On first launch, enter your Second Brain server address and log in with your credentials.
Sign in with your Second Brain account and download the APK.