Subtext from Subtext Video on Vimeo.

Subtext, a new iPad app for social networking platform in eBooks, has launched today. Like Kobo’s Reading Life, the app lets readers read and discuss books within the pages of a digital book with a community of friends. Readers can add links and have what the company is describing as “Facebook style discussions” around the book. Authors and scholars can also participate (Think DVD audio commentary for books). The above video goes into more detail about how it works.

The app is compatible with books purchased in Google’s eBookstore. Readers can open their Google eBooks in the Subtext app to contribute.

For launch, Subtext partnered with various publishers including Hachette Book Group, Penguin Group and Random House to offer 18 books that already include author conversations and notes. Books included in this are A Game of Thrones, Incognito, Snow Flower and The Secret Fan.

The company was financed with $3 million in seed investment from Google Ventures, Mayfield Fund, New Enterprise Associates (NEA) and Omidyar Network.