Boo.ai is a minimalist AI-powered writing assistant that uses GPT-3 technology to generate text based on natural language prompts. It offers features such as smart autocompletion, custom prompts, and built-in templates to help users write faster and better. In addition, Boo.ai provides professional feedback and suggestions for improving style, tone, and structure. Boo.ai uses Markdown for formatting and has a simple text editor interface. Pricing plans start at $8/month with a 3-day free trial.