The number of teens who own smart phones has nearly tripled over the last two years, says a new study: About 4.8 million teenagers owned smart phones in April of this year, according to research firm ComScore; in April 2009, only 1.7 million teens owned smart phones.

Currently, 28.7 percent of teenage mobile-phone users carry smart phones, and analysts expect the number to rise above 50 percent by next year, according to The Boston Globe.

The increase in teenage smart-phone use follows an industry trend. Last week, Nielsen released a study that found 55 percent of new mobile phone purchases by consumers were smart phones. That was up from 34 percent in 2010.

In the teen study, Google's Android operating system led the way with 36 percent of the teen smart-phone market owning Android-based phones, according to ComScore. Apple iPhones followed with 29 percent, and Research in Motion's BlackBerry phones were third, with 23.8 percent.

While the teen smart-phone market is growing, parents are still bearing the brunt of the financial burden. The study found that only 9.3 percent of teens pay their own cell phone bills, and 76.5 percent are on family plans.

Check out Consumer Reports' smart phone Ratings (available to subscribers) to find out how the latest models performed in our tests.

Number of teens with smart phones surges [Boston Globe]