4. Half of iPhone Users Are Under age 30 Source: Rubicon Consulting, March 31, 2008. http://rubiconconsulting.com/downloads/whitepapers/Rubicon-iPhone_User_Survey.pdf
5. Most iPhone Users Had Previous Apple Experience Source: Rubicon Consulting, March 31, 2008. http://rubiconconsulting.com/downloads/whitepapers/Rubicon-iPhone_User_Survey.pdf
6. Most iPhone Users Are Technically Sophisticated Source: Rubicon Consulting, March 31, 2008. http://rubiconconsulting.com/downloads/whitepapers/Rubicon-iPhone_User_Survey.pdf