In today’s mobile news roundup: Softbank reveals plans to acquire Sprint; Microsoft Office 2013 coming to iOS and Android by first quarter of next year; HTC pulls out tablets in the US; and FCC approves Kindle Fire HD.

Softbank to acquire Sprint

Softbank, the Japanese mobile carrier, is said to be in the final stages of acquiring US carrier Sprint Nextel in a deal that would exceed $12.81 billion in value. If the deal pushes forward, it can help Softbank expand outside Japan where it is currently the third largest network carrier in terms of subscribers.

The acquisition may solidify their hold in Japan’s mobile market while also opening up a whole new world of possibilities. Earlier this month, they announced that they would acquire rival eAccess for $1.84 billion to expand their 4G LTE coverage.

Microsoft Office 2013 coming to iOS and Android by first quarter of next year

According to Czech tech news site IHNED, Microsoft will be releasing the iOS and Android versions of their Office 2013 during the first quarter of next year, after March. Petr Bobek, Microsoft Office portfolio manager in the Czech Republic, also added that Office 2013 will be first made available to companies and Microsoft partners by December 2012 while the consumer release would be available by February 2013.

But don’t get too excited: the rumor was denied by Microsoft’s head of corporate communications, Frank X. Shaw, stating that the information shared by their Czech subsidiary was not accurate.

HTC pulls out tablets in the US

Taiwanese company HTC conceded defeat as they pulled out their tablets in the US market, stating that they cannot compete with Apple’s iPads. According to HTC’s global online communications manager, Jeff Gordon, despite the pullout, they’re still watching the US tablet market closely. There’s still a possibility for a tablet comeback if they come up with a tablet that can “make a splash.”

“It was a great learning experience for us, and they definitely met expectations,” Gordon said.

FCC approves Kindle Fire HD

Amazon unveiled the Kindle Fire HD even before the Federal Communications Commission approved the 4G version of the tablet to be sold in the US.  Amazon then promised their consumers who pre-ordered the 4G tablet that they would ship them once the FCC approves. The FCC has now approved the tablet and Amazon customers will probably be getting their 4G tablets soon.