The company, which runs the Firefox browser, has partnered with Chinese low-cost chip maker Spreadtrum.
"In 2014, we are differentiating our user experience and our partners are growing the portfolio of devices. We are also enabling a whole new category of smartphone, priced around USD 25, that will bring even more people around the world online," Mozilla Chief Operating Officer Jay Sullivan said.
Firefox OS devices are the first devices built entirely to open Web standards, with every feature developed as an HTML5 application.
"We launched our first smartphones in July, and have since expanded into 15 markets. People in Latin America and Eastern Europe have eagerly upgraded from their feature phones to Firefox OS smartphones. Sales have far exceeded our targets. But 2013 was just the beginning," Sullivan said.
The devices from Mozilla's stable are expected to see stiff competition, especially from Chinese and Taiwanese handset makers like Huawei and ZTE.
Since last year, Firefox OS devices have gone on sale in 15 markets with four global operators and handsets from three manufacturers.
Firefox OS will be expanding into important new markets in 2014.
However, no details on the availability of the devices in India was disclosed.