"كتاب فن البيع" or "The Art of Sales Book" is a comprehensive guide to mastering the art of sales. The app, developed by Osman Abdelrhman, is available on Android for free. The book provides insights into the principles, secrets, and fun of sales, and lays down the rules and explains the secrets, delving into humor, preparing to impress the potential customer, and building relationships and communications.

The book includes tips on delivering exciting presentations, handling objections, closing deals, and following up with clients. Along with these, the book also covers customer service, networking, public exhibitions, the network of relations, leadership, the benefits of increasing income, and responding to invitations.