Text-to-voice technology has a long history. The famed technologist Ray Kurzweil created an early reading software product in 1976, which in 1996 led to the founding of Kurzweil Educational Systems, a leading maker of reading software for PCs and Macs.

However, the Kurzweil software costs as much as $1,500 a seat, while some of the other PC-based text-to-speech products cost $50 to $70, Chen said. “We charge $10 for the app, plus $2 or $3 for a voice,” he pointed out. He hasn’t actually written his own text-to-speech software, instead taking advantage of commercially available software for mobile devices that is approaching commodity pricing, combined with his own user interface. Alternate voices for the app are sold separately. […]