Mozilla Firefox announced several key carrier and manufacturing partnerships that may give it a fighting chance at gaining a foothold in the smartphone market.

Mozilla makes for an interesting new player in this space, particularly in emerging markets overseas It announced Sunday at the Mobile World Congress that it will work with carriers such as Deustche Telekom, KDDI, Telefonica and Sprint around the world to offer another smartphone platform to consumers.

Right now the platform war for mobile devices essentially comes down to two options: Google’s Android or Apple’s iOS. Their closest competitors are Microsoft’s Windows Phone and BlackBerry’s smartphone platform BlackBerry 10, but even those major companies are going to have to fight hard for a third-place spot.

Mozilla’s plans aren’t nearly as grand, but the phones are launching in growth markets such as in Brazil, Mexico, Poland and Spain. More markets, the company said, are coming soon.

In addition to signing an impressive array of providers, Mozilla has also made agreements with major manufacturers, including a deal to put its Web-based operating system on phones from ZTE and Alcatel. On Sunday, the company announced new partners LG and Chinese smartphone maker Huawei. Sony also said that it’s exploring making a Firefox OS handset in the future.

Sony had plenty to announce, as well, most notably the U.S. availability of an Android tablet called the Xperia Tablet Z. The company first showed off the device, which runs Google’s Android operating system and has a 10.1-inch display, last month but said Monday that it will come to the United States this spring. It measures just under 0.3 inches thick and will cost $499 for a 16 GB model. A 32 GB model will cost $699. Like other Xperia gadgets, the tablet will also be water-resistant. Sony said it can withstand being submerged up to three feet for up to half an hour. The company also announced new Cyber-shot digital cameras.

In other tablet news, HP also released a new tablet — it’s first consumer-focused slate since it discontinued the TouchPad tablet last year. HP’s TouchPad got high marks for its software, but its hardware left much to be desired.

The new tablet, called the Slate7, is aimed squarely at the market for the iPad mini and will run Android. It will cost $169 and is expected to go on sale in the United States in April.

HP also marked its reentry into the consumer tablet market by announcing the sale of the WebOS platform that powered the ill-fated TouchPad and HP’s old Palm devices. According to a release from the company, it sold WebOS to LG, which will use the system to power its smart televisions. Under the agreement, the company said, LG will keep WebOS as an open source project for developers. HP, meanwhile, will retain Palm’s cloud computing assets and will remain responsible for supporting Palm users.

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