San Diego-based KidZui, a venture-backed developer of kid-friendly browsers, has rolled out a new iPhone version of its service. The firm said today that its ZuiTube App, which is free, offers kid-safe, user-generated videos. The service is targeted at kids ages 3-12, and is an iPhone version of its existing, ZuiTube video site. KidZui is backed by Emergence Capital Partners, First Round Capital, Maveron and the Scholastic Corporation.