Rewrite or reply to your messages before you send them, choosing from safer, funnier, or custom tones
The AI Book Agent
Stage
Startup
Startup
Founded
Not given
2024
Based in
Not given
GB
Pricing model
Freemium
Freemium
Pricing
Free: $0 forever for on-device rewrites with unlimited rewrites, no account required. Pro: $3.99/month or $39.99/year; new subscribers get a 14-day free trial and can cancel anytime.
Free: 100 welcome credits. Plus: US$29/month with 1,000 credits per month. Pro: US$59/month with 4,000 credits per month. Max: US$99/month with 10,000 credits per month. Yearly option saves 2 months (one payment for 10 months of the monthly price).
Key features
Safer tone that clarifies and reduces hostility
Funnier tone that changes register
Custom tone by typing your own instructions
Cloud rewrites for Pro subscribers
How I Sound feature to apply your voice to rewrites
Support for longer drafts on Pro
Works in iPhone keyboard and as an app
Write from documents, notes, talks, recordings, or ideas
Support for 100+ languages
Multiple input formats including PDF, Word, MP3, MP4
AI-powered chapter writing
Built-in editor with chat interface
Export in multiple formats: DOCX, EPUB, PDF, HTML, KDP pack
Cover and illustration generation
Specialized book skills for memoir, novel, biography
Unlimited web search for research
Unlimited book storage
What makes it different
Never sends messages automatically—you always copy and send manually
Drafts never used to train models; privacy-first design
Free on-device rewrites with no daily limits or quotas
Works directly in iPhone keyboard for seamless workflow
You retain full ownership and commercial rights to your finished book
Content not used to train AI models
Start writing with just a sentence or bring complete materials
Free tier includes 100 credits with no card required
All-in-one workspace from drafting through publication