The Ping social network for music drew more than a million users in its first two days, Apple executives said.
Ping launched Wednesday and allows users to follow their favorite artists and interact with friends on message boards. The network dovetails with Apple's iTunes, the music download network.
Apple co-founder Steve Jobs unveiled Ping last week along with a host of other new products.
In addition to the iTunes services, Ping users can find concert dates, photos and videos and read concert and album reviews. One-third of those who use iTunes also signed up for Ping, the company said.
"As many more people download iTunes in the coming weeks, we expect the Ping community to continue growing," Eddy Cue, Apple's vice president of internet services, said in a statement.