The biggest differences between iPhone on Verizon and on AT&T are:
- On AT&T you can talk on the phone and be online (browse the web, send email etc.) at the same time.
- With Verizon, you can use the iPhone as a personal hotspot to create a Wi-Fi base station that allows connecting up to 5 devices.
- The volume and Ringer off switches are in a slightly different location on the Verizon iPhone so existing iPhone cases will not fit.
- Text messages longer than 160 characters get broken up into multiple parts on Verizon's CDMA network. AT&T's GSM network re-assembles them into a single message so it's easier to read.
- Verizon has better coverage over all than AT&T for cell phone service. AT&T's network is faster than Verizon's for data use.
These differences are explained in more detail below.
Plans and Rates
This chart (click to expand) compares the different plans available for the iPhone as of November 2011.
With the personal hotspot feature, the iPhone can be used as a Wi-Fi base station to connect up to 5 devices to the Internet. Verizon charges $20 a month for this feature and allows 2GB of data use. This fee is in addition to the cost of their data plan. AT&T does not price the mobile hotspot option separately. Their fee is $45 for 4GB of data, which includes data consumed as mobile hotspot or by the phone.
Talk or be online
The two iPhones are designed for different cellular networks - AT&T's is GSM and CDMA for Verizon. A CDMA limitation is that you cannot talk and be online at the same time. That means you can't simultaneously browse or send e-mail when on the phone. The Personal Hotspot feature also cuts off. On a 3G network, incoming calls take priority and interrupt your online connection but in a 2G area, you remain online and the call goes directly to voice mail. Text messaging is not affected by this limitation - you can talk and text at the same time.
Several users and reviewers have panned AT&T for poor coverage and dropped calls. Independent reviewers testing both phones have found Verizon's coverage to be better over all. There is, however, a possibility that with a surge in iPhone users, Verizon's network will experience the same bandwidth constraints that plague AT&T.
Having conducted tests for coverage and speed Wired found that AT&T download rates are 62% faster than Verizon, and AT&T upload rates are 38% faster than Verizon.
As of September 2012, Verizon has 4G coverage in the most number of cities. (see 4G coverage map) However, AT&T supports HSPA+, which is comparable to 4G in terms of speed and is in more cities. iPhone 5 supports HSPA+ and is the first iPhone to do so.
Globally GSM is a more popular network than CDMA. So chances are higher that your AT&T iPhone will work internationally - 220 countries for AT&T vs. 40 for Verizon.