Andrew Hoyle/CNET

Microsoft's Windows Phone continues to gain traction in the competitive smartphone arena.

For the three months ending April 13, Windows Phone captured 5.6 percent of all U.S. smartphone sales, Kantar Worldpanel ComTech reported Monday. That figure proved a healthy gain from the 3.8 percent share of sales for the same period in 2012.

Windows Phone is even winning former Android users, according to Kantar. Among people who bought a Windows Phone in the last year, 23 percent jumped ship from Android, while 25 percent upgraded from another Windows Phone and 42 percent moved up from a feature phone.

Microsoft is also seeing greater demand for Windows Phone from the younger crowd.

"When looking at those who changed device, between 2011 and 2012, Windows was more successful at capturing older consumers aged 50-64," Kantar Worldpanel ComTech analyst Mary-Ann Parlato said in a statement. "But when looking at those changing now and in the last year, we're seeing Windows now gaining share among those aged 25-34."

Microsoft can thank Nokia's Lumia devices for most of the gains in Windows Phone's market share, Kantar added.

The smartphone data comes from Kantar's U.S. consumer panel, which conducts more than 240,000 interviews each year. The information focuses exclusively on smartphone sales rather than market share.