Nuance today rolled out some interesting new facets to its developer program, NDEV, as well as its Dragon Mobile SDK, adding support for Windows Phone 7 and a tiered premium program.

Matt Revis, head of product management for Nuance, says the company has seen an unexpected amount of interest from developers looking to integrate Nuance’s text-to-speech and speech recognition technologies.

“I think we thought that we were meeting the demands of a small group of mobile app developers… and I think we’ve way underestimated that… We’ve seen thousands of mobile developers entering this program,” Revis says.

Nuance reports that NDEV Mobile already has signed on more than 4,000 iOS and Android developers since its release back in January.

NDEV now includes a three-tiered program for developers that includes Silver, Gold and Emerald levels.

Silver users get full access at no charge to Nuance speech recognition and text-to-speech technologies, while Gold members will incur a per user charge for the service but also have access to SSL encrypted data transmission, an HTTP web services interface  and a more comprehensive SLA support offering.

On top of that, Emerald users will get the full hands-on treatment with a highly customized plan that includes a service manager, custom language models and access to all of Nuance’s APIs. Pricing for Emerald customers is determined on a case-by-case basis.

Revis points out the success of the program, noting that virtual assistant Siri, one of the first developers to work with Nuance, was ultimately acquired by Apple. The company has also worked with Amazon, Ask for iPhone, Merriam-Webster, Dictionary.com and Yellow Pages, among other big names.

The Dragon Mobile SDK is available for iOS 4.0 (iPhone/iPad/iPod touch), Android 2.1 and higher, Windows Phone 7.1 and via an HTTP web services interface.