Free: 4,000 daily credits (approximately 2-3 emails per day), or 30-day Premium trial. Premium: $9.90/month (unlimited emails) or $81.90/year (25% savings).
Octavo: Free forever (1 project, 3 research files, limited AI usage). Quarto: $20/month or $200/year (unlimited projects, 50 files per project, 10× more AI usage). Folio: $100/month or $1,000/year (unlimited research files, 5× more AI usage than Quarto, priority queue, early access to new models).
Key features
Analyzes incoming emails and generates personalized response suggestions
Adjusts tone based on context and intention
Smart mode requires minimal input from user
Works with Gmail and Outlook
Chrome extension integration
Supports email creation from scratch with context input
Daily credit system for free users
Context-aware AI suggestions that read your chapters first
Source-grounded edits from PDFs, URLs, and YouTube transcripts
Red and green diffs requiring your approval
Export to Amazon KDP, Apple Books, Lulu, IngramSpark, Google Play Books, Draft2Digital
Chapter-aware AI agent
Citation engine with Chicago-formatted bibliography
Front matter and back matter editor
Version history to save and restore manuscript versions
Clean PDF and EPUB export with professional typography
What makes it different
Specialized focus on professional email writing rather than generic AI writing
Context-aware and context-specific response generation
Easy-to-use interface designed for professionals
Immediate data deletion for privacy protection
Keeps your entire book and research in context, unlike chat windows that start fresh each session
Returns edits as approvable diffs you control, not auto-inserted changes
Built specifically for book publishing with real front matter, back matter, and professional export formats
Scribbly
Chaptora