Symbian posted strong first-quarter results, with 11.7 million phones containing the Symbian OS shipping during the quarter ended March 31. The company calculates a total of 70.5 million Symbian OS smartphones have shipped to date.

The 11.7 million shipments represent a year-over-year increase of 73 percent, according to Symbian, which reported 6.75 million units shipped in the same quarter a year ago.

Revenue reported for the quarter was $67.5 million, up from $43.1 million, according to the latest numbers coming out of Symbian.

Symbian reports 56 Symbian OS phones were in development by nine Symbian OS licensees during the quarter, with 11 new models and variants being shipped for the first time during the first quarter.

Symbian is a joint venture between Nokia, Ericsson, Sony Ericsson, Panasonic, Siemens and Samsung.