From the site:
Wattpad is the world’s largest community for discovering and sharing stories. It’s a new form of entertainment connecting readers and writers through storytelling, and best of all, it’s entirely free.
With thousands of new stories added every day, an incredibly active community of readers, and the ability to read on your computer, phone, or tablet, Wattpad is the only place that offers a truly social, and entirely mobile reading experience.
Writers use Wattpad to connect and engage with our monthly audience of over 10 million readers to share their work, build a fan base, and receive instant feedback on their stories. More than 500 writers have published pieces that have been read more than a million times.
Wattpad provides a completely freeing writing experience, allowing writers to publish their work serially, to write from anywhere using a mobile device or tablet, to collaborate with readers and other writers, and to see their work gain appreciation and inspire fans to create cover art or even video trailers.