Oyster, an ebook subscription service, recently topped the half-million title mark. Its major competitors, Scribd and Entitle, offer far fewer with 300K on Scribd and 125K on Entitle.

Any of these subscription services can enhance an author’s career. They are focused on discovery, so they help readers find your titles. My own three titles have been available on Scribd for only a few months, and already they have achieved a surprising number of reads…without any additional advertising push.

Subscriptions offer smaller payments than purchases but if you’re looking for eyes on your work, these services can help you enhance your visibility and provide a modest income at the same time.