Firefox Operating System and Telefónica just made a deal to bolster its entry into the burgeoning Latin American wireless market.

Telefónica and FireFox just announced a partnership with Line, a calling and messaging app, that will give Telefónica subscribers with Firefox OS phones exclusive access.

The partnership with Line is a move by Spanish and Latin American telecom giant Telefónica and upstart third-party mobile OS company, Firefox OS, to give their customers, exclusively, a little something extra for choosing something besides an iPhone or Android.

Line is an app that gives users free voice calling and free video calling for smartphones and desktop PCs over the internet -- a boon for families and friends countries apart that want to keep in touch without running up the phone bill or hassling with phone cards -- as well as games and a cute messaging system. The partnership will bring Line apps to Telefónica subscribers in Venezuela, Peru, Spain, Colombia, Uruguay, Brasil, and Mexico, with additional markets "to be announced shortly," according to Telefónica.

"This agreement marks the start of an exciting partnership between LINE and Telefónica. Telefónica is fully committed to bring the value of Firefox OS to our consumers and is already seeing this ecosystem as a fast growing customer base," said Francisco Montalvo, Director of Group Devices Unit, Telefónica South America. "LINE's messaging app enables us to strengthen what we are already offering our customers and will open up even more collaborative opportunities in 2014."

Line, which has previously been available in its home country of Japan, has an opportunity to snag a lot of new users: according to TechCrunch, Telefónica has 320 million global subscribers, many of which are in Latin America. Firefox OS is also poised to gain from the partnership, offering current and potential customers Latin America an exclusive tool that could increase its traction in that market.

Firefox OS launched in Latin America and Spain with Telefónica last year, offering relatively low-cost prepaid and on-contract smartphones installed with Firefox OS. The Latin American move by the upstart OS was partially because developed smartphone markets in the U.S. and other places are already polarized between Apple's iOS and Google's Android operating system, making it hard to create inroads to any markets besides niche buyers.

Latin America, however, is ready to explode with mobile technology. As we previously reported, a 2012 World Bank study showed that Latin America leads the world in mobile growth, with more than 84 percent of Latin Americans subscribing to a mobile service, and about 98 percent signal coverage. But as feature phones running basic wireless internet are still common, there's plenty of room for smartphone growth for a young mobile OS to be found in first-time Latin American buyers.

Besides going for low-cost and emerging tech markets, Firefox OS provides a bonus for carriers such as Telefónica, in that its open-source operating system (and the fact that it's not a giant like Apple or Google) gives wireless carriers a lot more say in what apps run on smartphones in their networks.

Telefónica says Firefox OS smartphones preloaded with Line will be launched in early Q1, and Firefox will also include Line in new versions of the OS released to existing Firefox OS users in Latin America.