As satisfying as volunteering is for many of us, the time commitment can often limit opportunities to do good.

And though the Internet, through websites like VolunteerMatch.org, has made it easier to match needs with those willing to provide solutions, the idea of micro-volunteering had few broad-minded advocates until Jacob Colker. In 2007, Colker co-founded, with Ben Rigby, the San Francisco-based organization known as the Extraordinaires. Later rebranded as skillsforchange.com, it featured one of the first smartphone apps enabling volunteers to donate a few minutes of spare time to charitable community groups and other nonprofits in need.

“For the most part, traditional volunteering opportunities require a commitment of time, but we created a marketplace where it was easy for