Apple tweaks its iPhone lineup (or else).
Fears of Apple's decline in the short-term are overdone, but this much is true: The iPhone powers earnings, and the growth opportunity has shifted to emerging markets. To keep Android from dominating there, Apple will have to design and release a new kind of iPhone that's less expensive and more cloud dependent.
Samsung presses its independence (from Google).
No single company has benefitted from Android more than Samsung. But for the mobile giant's gains to stick long-term, it will have to develop an ecosystem of its own and reduce its reliance on Google. Look for Samsung to start doing exactly that in 2013, as new EVP David Eun returns to Silicon Valley from a year in South Korea and gets down to business.
Enterprise accelerates PC's decline.
The single most significant trend in tech is the decline of the PC ecosystem. It's hurting not only PC stalwarts like Dell and Hewlett-Packard, but also accessory makers like Lexmark and Logitech. It will get much worse in 2013, as enterprises hold off adopting Windows 8 and buy other tablets instead, accelerating the decline of the PC ecosystem.
Year of the shakeout (some big companies on the bubble fall off).
Which brings us to this: Like a tragic game of musical chairs, some companies that can't find a place in a strong mobile ecosystem will crumble in late 2013. Most at risk: Barnes & Noble, HP, Nokia, and Research In Motion.