After 11-year-old Cameron Cohen had surgery for a benign tumor on his leg, he turned his passion for computers into creating an iPhone app, called iSketch, that lets people draw on a computer screen. Cohen donated much of the profits from the app to Mattel Children's Hospital UCLA so the hospital can buy electronic gear for other sick children. The iSketch is now available through the iTunes Store for the iPod Touch and the iPhone. He also requested that Mattel Children's Hospital buy more interactive electronic devices for teens and tweens, said hospital officials.