– Google, Facebook, Amazon, and Apple are widely considered the kings of digital world. But as they look to grow further, increasingly they will need to target each other's turf, dramatically raising the stakes in cyber conflicts in 2013, reports the Wall Street Journal. Google. Perhaps the most wide-ranging of the giants, it's clashing more and more with rivals in telecommunications and cable TV. Thanks to its $12.5 billion purchase of Motorola, expect Google to expand in all aspects of Android and smartphones. (It also wants to take most of Microsoft's Office business, notes SlashGear.) Amazon. The Kindle Fire HD (running on Google's Android) has garnered raves and earned a strong niche versus Apple's iPad. But rumors are swirling that 2013 will be the year Amazon brings out a smartphone of its own. Facebook. With the social network rewriting its code for mobile devices, many predict that a move into hardware will be coming any day now, even though Mark Zuckerberg has repeatedly denied it. Also expect to see Facebook getting more aggressive with its own search technology and online retailing. Apple. Apple may be king of the tech hill these days, but many experts say that just gives the company more areas it needs to defend. But Apple isn't only playing defense, and is increasingly looking to move into TV.