The new iPhone 5 may use Verizon cellular data while connected to a Wi-Fi network. Be sure to check your bill for data overage charges.
According to Verizon spokesman Torod Neptune the iPhone 5 may use Verizon cellular data while the phone is connected to a Wi-Fi network. He advised iPhone 5 owners to download the Apple has a fix. He confirmed that Verizon Wireless customers will not be charged for any unwarranted cellular data usage.
This carrier settings update resolves an issue in which, under certain circumstances, iPhone 5 may use Verizon cellular data while the phone is connected to a Wi-Fi network.
To install Tap Settings > General > About. Wait for the following alert that says "Carrier Settings Updated." Tap OK to install the update. Hold the Sleep/Wake button down until you see "slide to power off". Slide to power off. After the device powers off, hold the Sleep/Wake button to turn your phone back on.
To finish the installation of the update you must turn your iPhone 5 off and then on again.
This is not the first glitch discovered for the iPhone 5, iPhone maps have been criticized for lacking some towns and having in accurate information. The new iPhone does have a better green rating than previous models. It's toughest competitor is the Samsung Galaxy S III (read comparison).