Steve Jobs began development of the iPhone in 2005 as CEO of Apple, steering its focus away from a tablet. Apple created the iPhone in secret collaboration with AT&T Mobility. The iPhone evolved through several models - the original iPhone in 2007, the iPhone 3G in 2008, the iPhone 3Gs in 2009, and the iPhone 4/4s in 2010 and 2011. Customer reviews showed the iPhone received excellent ratings on AT&T, Verizon, and Sprint, which all offered unlimited talk, text, and data plans for the iPhone at the time.