* Paid plans include premium AI narrators and the Celeste tutor powered by leading models.
An AI companion who reads what you’re reading
Celeste stays tied to the text in front of you, whether that is one file, a saved set, or your whole library. Ask for summaries, definitions, and links between chapters without losing the thread. Share parts of those chats with friends when you want to compare notes.
All your reading, in one place
Upload from your computer or pull from Google Drive, Dropbox, and other folders you already rely on.
Open PDFs, EPUBs, and plain text on the web, and pick up the same titles on phone or tablet when you sign in.
Immerse yourself in what you’re reading
Step away from the desk and keep the thread: voice-first chats with Celeste, highlights, and quick questions while you walk or commute. Your marks sync back to the same file when you return to the screen.
Share the joy of learning with your friends
Share reading logs and notes with people you trust so you can read in parallel and compare takeaways. Treat books as shared reference points for group projects, book clubs, and study circles.
Straight answers
Which files can I upload?
Trellis works with PDFs, EPUBs, and common text formats. You can upload from your device or connect cloud storage you already use.
How is Celeste different from a general chatbot?
Replies draw on the book or document you have open, so explanations stay tied to the page instead of generic answers.
What sits behind the paywall?
Free tiers let you try core reading and Celeste features. Premium adds advanced narrators and tutor depth. Check in-app pricing for current bundles.
Where can I use Trellis?
The web app runs in your browser. The iOS app is on the App Store, and other platforms may roll out as the team finishes testing.