There are plenty of ebooks on the market, but "The Silent History" pushes the envelope for what a fully interactive ebook can be and do.

It's much more than digitized text. Part book, part treasure hunt, it immerses readers in the story in new ways.

"The Silent History" was created for the iPad/iPhone, and an Android version is in the works.

The plot centers on a mysterious epidemic of children who are unable to speak. Each chapter is called a "testimonial" and told from the point of view of people affected by the outbreak -- parents, doctors, teachers and others.

The book is released in serial form: there are six parts -- each with 20 short chapters released every weekday over a month. There's a month's break between episodes, so the action unfolds over a year.

There also are extra features called "field reports" -- short segments designed to enhance and deepen the narrative, which are set in real locations and feature real-world landmarks. To access these, the reader has to be physically present near the area where the field report is set, and have his/her tablet or phone's GPS match the location's coordinates. For example, the report might mention a specific object, such as a fence or a window, and the reader will see it in real life as they read the field report.

Readers don't need to have the field reports in order to appreciate the book's main narrative. The app's creators aim to expand the reach of the field reports section and are inviting people to submit their own reports from locations not currently part of the "The Silent History" project.

The app is $1.99 for the first monthly installment of the book and $8.99 for the entire book.

www.thesilenthistory.com

Robots for iPad is a new app that explores the diverse world of robots with an extensive collection of color photos and information. It will appeal to anyone interested in learning more about robots and technology and is a great introduction to the world of robotics for kids.

The app features information on 126 robots from 19 countries, with specs and articles about each.

There are nearly 500 photos. Swiping the touch screen creates 360-degree views of some of the robots, and users can use the interactive screen to get them to move.

Other features include videos of robots in action, audio interviews with leading roboticists and news updates from the field of robotics.

Robots for iPad was created by the technology magazine IEEE Spectrum.

It's available for iPad and iPhone on iTunes ($4.99).

http://robotsforipad.com