With familiar names like Apple, Google, and Facebook usually drawing the spotlight, it's easy to forget one of the tech world's old pleasures: the story of how somebody with a modest idea can take an innovation and run with it.

Maybe it won't change the world or make billions. But the Internet gives even a small idea a shot to find a market in ways that inventors of the past couldn't imagine.

Here's a look at two small inventions that seek to piggyback on the popularity of Apple's iPhone in the busy "iPhone accessories" market, an alluring place for inventors.

An iPhone case plus "oops" protection. Mike Kane didn't own an Apple phone until the iPhone 4 came out in June 2010. Now he's on his third, though he insists his own experiences dropping them — "all basically phone-to-concrete" — have little to do with his new product, the $45 CellHelmet.

Maybe so. But when Kane, 29, decided to branch out from selling other companies' smartphone accessories on his website, CellPig.com, and create one of his own, he focused on an idea he might have appreciated himself.

Kane, of Greensburg, Pa., and a friend launched CellPig last year, six years after he graduated from the University of Pittsburgh and two years after they got a start on eBay. They knew smartphone cases were a popular product, and they knew why: Without a carrier's discount, an iPhone is a $500-plus investment. They also noticed that the best cases seemed to share a shortcoming: they resembled a brick.

"All the super-protective iPhone cases are really, really bulky," he says. "We thought, 'Why don't we create a case that's really slim but that protects your phone better than a bulky case?' Then we thought, 'Well, duh.'?"

Thus was born CellHelmet's innovation: combining an iPhone case with a yearlong promise to repair a busted phone or replace it.

CellHelmet got off the ground with help from Kickstarter, which provides crowd-sourced funding for artists and entrepreneurs. The first units began shipping last week, and Kane says CellHelmets will soon be widely available at retailers as well as online.

Of course, replacement plans are also offered by wireless carriers, and many people choose wisely to self-insure against damage rather than pay. Nor is CellPig the first to offer third-party coverage. In fact, Kane uses data from one of his competitors to explain the value of CellHelmet.

Kane says that according to SquareTrade, more than 15 percent of iPhone 4 owners suffer phone damage during the first year, and four out of five of those involve cracked screens. Most of the rest suffer damage from water or other liquids.

CellHelmet protects against any damage except liquids, he says. Owners send the phone to a repair facility, and pay a $50 handling charge. CellPig promises that it will be repaired or replaced with a refurbished phone and returned, by overnight shipment, within three business days.

It's not comprehensive, but it protects against the most common damage and costs little more than a basic case, Kane says. "You're basically getting a new iPhone for $95, which I think is worth it," he says.

For the record, I've had three iPhones and never broken one, despite repeated drops. But I've also never left one in my lap as I got out of a pickup truck.

Help for the ham-handed. Unlike Kane, Jerry Rosengarten has owned iPhones since the start. But the New Yorker, an entrepreneur whose other ventures include developing office buildings and owning a restaurant, has also had an iPhone problem from the start: typing on a virtual keypad.

He first introduced his answer two years ago: the 4iThumbs, a $30 plastic overlay with raised bumps that guide your fingers to the right places, sold via his website, 4iConcepts. When not in use, it slides off the front of the phone and onto the back.

This year's version, renamed the Invisible Keypad, works much the same as the original. A series of improvements have centered on making the overlay easier to slide off the front of the phone and stow on the back. Starting in July, it will stow beneath a sliding back cover.

Rosengarten says some people use the Invisible Keypad to adjust from a BlackBerry or other devices with physical keyboards, like training wheels on a bicycle. Others, like Rosengarten, leave it on most of the time. A key market "is for people who like to feel the keys — big texters who barely use the phone," he says.

Rosengarten is planning a version designed for the iPad and another that will adhere to the front and back of an iPhone, so that it will work with any case.

"Steve Jobs was right. You can type pretty well with a flat screen," Rosengarten says. "But you have to get used to it — and this product helps you adjust."

Contact Jeff Gelles at 215-854-2776 or jgelles@phillynews.com.