The tool, called Intro, pulls details from the profiles of LinkedIn's more than 238 million users so the recipient of an email can learn more about the sender.
The information will be limited to what the email senders already allow anyone to be seen on their LinkedIn accounts, unless they already have granted the recipient broader access through a connection on the service.
The feature works with Gmail, Yahoo Mail, AOL Mail and Apple's iCloud when any of them are plugged into the iPhone's built-in email app. LinkedIn plans to update the feature so it also works with Microsoft's Outlook.com and Exchange email. Intro also works on Apple's iPad, although the feature isn't tailored for that device. LinkedIn eventually will release a version of Intro designed especially for the tablet format.
LinkedIn imported the technology powering the Intro feature from its acquisition last year of Rapportive, a startup that had already been mining online social networks to include personal information in correspondence sent to Gmail accounts.
Intro is part of LinkedIn's push to make its network indispensable on mobile devices as more people manage their personal and professional lives on smartphones and tablets.
LinkedIn says about 38 percent of the traffic to it networking services now comes through mobile devices, up from just 8 percent in early 2011. LinkedIn CEO Jeff Weiner predicted that mobile devices would be reeling in more than half the service's traffic at some point next year.
As part of its effort to make its network more alluring on mobile, LinkedIn also released a new version of its service's app for the iPad.
LinkedIn's strategy has been paying off since the company went public nearly two-and-half years ago. The Mountain View, California company has consistently been delivering earnings that exceed analyst projections, helping to lift its stock by more than five-fold from its initial public offering price of $45.
The shares shed $3.60 to $241.35 in Wednesday afternoon trading, as the broader markets ticked down.
