More challenging is dealing with expensive data connections, something Zuckerberg posed as a bigger barrier than smartphone affordability.
Chris Weasler, whose role at Facebook is to improve access to Internet services around the world, said he has met many smartphone owners who forgo data services and use the devices instead as mobile computers and cameras.
Local wireless carriers will need to better educate their customers on the value of connectivity, he said, while app developers need to tweak their services to work on slower, less reliable networks. He said Facebook learned that when a team went to Africa and couldn't use Facebook's Android app because it pulled too much data.
Firefox phones have FM radio tuners built in so owners won't waste data connection on streaming services, while another emerging system, Ubuntu, tries to make sure it has apps that work well offline.
To address the lack of credit cards in emerging markets, Nokia replaced Android's card-based app store with one that permits billing directly to mobile operators.
Ultimately, companies need to figure out what to sacrifice to bring costs down. Forget high-resolution video or a giant screen, such as the 5.1-inch display on the Samsung Galaxy S5 that was announced Monday. Not only are those features expensive, they require faster processors and longer battery life, adding to expenses.
Cellular connectivity through 4G is also something often dropped, as many emerging markets are lucky just to have the slower 3G.
But what's good enough? Leo Li, CEO of Spreadtrum, said phones using his company's blueprints work as good as Apple's iPhone 4. But that's a 4-year-old phone. Nonetheless, he said performance is better than the basic phones that first-timers are upgrading from.
By upgrading, people can truly access the Web and aren't limited to the few services that phone makers already included.
"To spend a little more for a true Web experience is pretty good, even if the resolution isn't as good as the iPhone," said Jay Sullivan, Mozilla's chief operating officer. "People want to be connected. They want to be online and have access to all the information and all the things we do, like maps, as they explore new places."
