A new study from research firm NPD Group said that while cell phone sales may be on the decline in the United States, retailers may be able to make up for it with accessory sales, RCR Wireless News reports.

(That's certainly in line with all the radio commercials we're hearing lately about how easy it is to "start a business making thousands of dollars per month selling phone accessories you don't even have to pay for!" But we digress.)

The report said that cell phone purchases declined 20% year-over-year in the U.S. from January through April—but about "half of customers are likely to turn to retail establishments like mass merchants and electronics stores for accessory purchases."

"With saturation increasing and the pace of new phone adoption slowing, there's still room to increase revenues from the sale of mobile-phone accessories like Bluetooth headsets, memory cards and car kits," said Ross Rubin, director of industry analysis for NPD, in the article.