The iPhone
Though Android may occupy a larger cut of the market these days, Jobs must be credited with turning the moribund cell phone market upside down. With the iPhone in 2007, Apple introduced a device that pioneered the smartphone revolution thanks to a minimalist design, large responsive touchscreen and solid operating system that blew Palm and RIM's efforts away.
Jobs was involved in every step of the initial development process, which according to one insider cost the company $150 million. He also pushed for unprecedented control over the device's construction with Cingular (now AT&T) executives -- which is why the iPhone doesn't carry an AT&T (or Verizon) logo on it. Users also have Jobs to thank for Visual Voicemail, which chucked the standard voicemail system for a non-linear "push to listen" interface, a feature other smartphones now have too.