Innovation in the gadget business rarely comes in great leaps forward. Most of the time, somebody will take an existing idea and implement it at a cheaper cost, at a larger scale or in a new context, and that change is enough to shake up our sense of what technology can do.

And that's exactly what these five breakthroughs have done for me this year.

1. "Retina displays" grow up, and out. Two years after Apple's iPhone 4 introduced a display so sharp that you could no longer distinguish its constituent pixels, "Retina displays" started showing up in the Cupertino company's other gadgets (and many competing smartphones). On this spring's iPad, the results were amazing, instantly making the old model's screen look bad.

But on Apple's laptops, Retina displays have jacked up prices substantially. And on flat-panel TVs, ultra-high-resolution "4K" and "8K" resolution suffers from the fact that at typical couch-viewing distance, even mere HD resolution can exceed our visual acuity.

2. Cheaper smartphone service. This year, the cost of keeping a new smartphone finally started ratcheting down in a big way. The prepaid carrier Cricket Wireless slashed the monthly bill for an iPhone to $55, then its competitor Virgin Mobile beat even that with a $30 deal.

DNEWS VIDEO: Gadgets and Gizmos

Among the four major carriers, Verizon Wireless may have hiked its rates but T-Mobile has gone in the other direction with "value" plans that subtract the usual subsidy of a cheaper phone price, meaning you save more over time. And next year, that carrier will make that its standard.

3. Affordable gigabit broadband. While most Americans are stuck with the same one or two broadband Internet providers as ever, a lucky few can now sign up for breathtakingly faster connections at prices no higher than a low-end cable bill: charges just $70 for gigabit (1 billion bits per second) service in parts of the Bay Area, a price matched by Google's gigabit-fiber service in Kansas City.

Sure, most of us can't use those speeds. But imagine what the arrival of gigabit access for under $100 would do to your own ISP's pricing… or don't, if you'd rather not depress yourself.

4. Smarter shared transportation. Near-ubiquitous wireless-data service and cheap GPS sensors are making it easier and cheaper to get around cities without having to own your own ride. Among the most interesting such options: car2go, which broke out of its Austin test market this year with a launch in Washington this spring, followed by expansion to Miami, Portland, San Diego and Seattle. It allows you to rent a Smart fortwo at a cheap, per-minute rate and then park it on the street for free — in effect, making it a longer-distance complement to bicycle-sharing services like D.C.'s Capital Bikeshare.

I'm equally fascinated by startups that make better use of transportation we've already paid for, such as the Uber sedan-ride service. But when these involve privately-owned conveyances — for instance, Lyft's carpooling — they can run into legal hangups.

5. The Internet winning in Washington. One of the tech business's most promising developments didn't involve software code or circuit boards. But the way Internet users rebelled at the offensive overreach of the Stop Online Piracy Act, which would have broken the Net's basic routing system and allowed copyright holders to unplug the finances of allegedly infrinting websites pretty much at will, mattered anyway.

"SOPA" had the backing of some of Washington's most entrenched interests, but individual citizens who didn't want to see technology criminalized overcame all of it. That's good news for continued innovation, both next year and over the next decade.

Credit: Corbis Image