Novel Effect’s effort to bridge the real world of books with the digital world makes a lot of sense right now: we’ve quickly gotten comfortable with voice recognition in our daily lives, from Siri on Apple’s iPhones to Alexa on Amazon’s Echo speakers. A little under a fifth of the population will use a digital assistant at least once a month this year, according to research firm eMarketer. And the people using these things the most are between the ages of 25 and 34. Chances are many of them have kids to read with.

Novel Effect knows this well: in Seattle, it is participating in the Amazon Alexa Accelerator, which is backed by Amazon’s $100 million Alexa Fund and is being run with accelerator Techstars.

To use Novel Effect, you open up the specific book in the app that accompanies the real-world book; this prompts the app to start listening for the book text so it can analyze your speech to figure out where you are in the story and synchronize all kinds of noises, from stomach-ache groans to neighs. It doesn’t require you to read the book straight from start to finish; you can start on page 10 and jump around if you want. And it doesn’t matter how much time you spend on one page, or whether you interrupt the reading experience to talk about things other than what’s on the page (Hammersley stresses that the app doesn’t record what users say, and is only looking for the book text).

By late this year or early next, the company also plans to offer a tool that lets anyone create new sound-enhanced stories or add sounds to existing ones.

My experiences with the current version of the app were mixed. I was charmed by the munching and a variety of other sounds in The Very Hungry Caterpillar; the timing was decent and the noises were appropriate. Yet when I tried reading Brown Bear, Brown Bear, What Do You See? it didn’t work nearly as well—tweeting and croaking interrupted my speech, spoiling the surprise of which animal would be revealed next.