Caribu is Free to get started! Caribu Free gives you access to 5 books/activities to get started.
If you're on a Caribu call with someone and read a book together, that will count as one book for each of you. If you open the book to the preview page, you can read the description of the book without using a credit. If you click the "read by myself" to read the book or if you read a book while on a call with someone, that will count as a book. If you want unlimited books and activities with your friends and family, you can upgrade to Caribu Unlimited at any time!