The new iPod nano with Multi-Touch

Apple dived into the competitive social networking business on Wednesday, introducing Ping, a service geared to music lovers that is built into iTunes, as it revamped its lineup of iPods and other products.

(Steven P. Jobs announced a new line of iPods, as well as Ping, a social media service based on music.)

Steven P. Jobs announced a new line of iPods, as well as Ping, a social media service based on music.

The company also introduced an upgraded version of its Apple TV set-top box that is smaller and, at $99, cheaper than its predecessor. It allows users to stream television shows from Fox and ABC for 99 cents, and it can also stream movies from Netflix and iTunes podcasts.

Along with the new iPods, which include upgraded versions of the Shuffle, Nano and Touch models, Apple introduced a new version of its mobile operating system, iOS.

At an event in San Francisco, Steven P. Jobs, Apple’s chief executive, said the new iPods represented the biggest upgrade to the company’s line of popular music players since they were first introduced in 2001.

“This year, we’ve gone wild,” Mr. Jobs said.

While the upgrades to the iPod lineup and to Apple TV were widely expected, Mr. Jobs surprised many in the audience with the introduction of Ping. The new social network will be instantly available to 160 million iTunes users, as long as they download the latest version of the software, which Apple released Tuesday.

In Ping, users will be able to follow friends and see what music they have downloaded or bought, what concerts they plan to attend and what music they have reviewed. They will also be able to follow bands and get updates on their new releases, concert tours and other events.

“Ping is for social music discovery,” Mr. Jobs said. “You can follow people and you can be followed.”

Mr. Jobs said Ping would have simple privacy controls. Anyone will be able to follow bands, and users will be able to say whether they want to be followed by anyone or only by people they approve.

The new iPod Touch is thinner than the previous model and comes equipped with front- and rear-facing cameras, as well as Apple’s FaceTime video chatting software. It also has the same high-resolution “retina” display that Apple first showcased on the iPhone 4 earlier this year.

The iPod Touch comes in three models. The 8-gigabyte version costs $229, the 32-gigabyte version is $299 and the 64-gigabyte version is $399. They will be available next week.