The iPhone, formerly exclusive to AT&T, makes its debut February 10^th for Verizon customers.  With so many complaints about dropped calls on AT&T’s network, Verizon could be landing a major knockout blow. The iPhone is nearly identical in most cases for both companies, but there are a couple of significant differences to point out.  Verizon uses a network called Code Division Multiple Access (CDMA), which runs voice and Internet over different tracks.  This means Verizon iPhone customers won’t be able to talk and surf the web at the same time.  AT&T uses a network called Global System for Mobile Communications (GSM), which allows users to talk and surf simultaneously with the networks ability to handle voice and data at the same time. This initially sounds like good news for AT&T, but Verizon’s network is what makes them a leader in the industry.  The CDMA network Verizon uses allows connection to multiple towers, which results in less dropped calls.  According to Consumer Reports Winter 2010, a reader survey tracked the two companies quality in 26 metro areas- Verizon led the charts in satisfaction for every city, while AT&T finished last for 19 of them.  AT&T is hoping that Computer World’s prediction of 26% of iPhone users switching to Verizon is wrong, but this is something we will find out over time.