To my knowledge that is not possible. I imagine you want to see how "fresh" the LinkedIn profile is?? The only LI app I know of that will show updates of other people is the Amazon Reading list (which will show updates made by your extended network).
Outside of that, LinkedIn has a "Joined Within:" search parameter. That won't show when they made updates but will let you know how long the person has had a LinkedIn account. Right now the "Joined Within" feature is kind of hidden. LinkedIn has a new search interface so you have to hit the Opt Out button at the bottom of the Advanced Search page.
In the future, if you want to keep tabs on when a candidate changes companies, try this site www.watchthatpage.com/ Just put in the direct URL to their LinkedIn web profile and WatchThatPage will check everyday to see if there are any changes.