The Apple iPhone, which is available in the United States through AT&T, Sprint, and T-Mobile, comes with a Personal Hotspot feature, which transforms your phone into a virtual router. When you enable your phone to act as a hot spot, you can share its data connection with other wireless devices. Hot spot technology is available on the iPhone 3G and later models.

Carrier Policies

Sprint, AT&T, and T-Mobile all have specific policies for Internet tethering. Before you can turn your phone into a router, you must ensure that your plan allows it. On AT&T, you must have a Mobile Share or a DataPro 5GB plan. If you use Sprint, you will need to purchase a Sprint Mobile Wi-Fi Hotspot add-on package. With T-Mobile, the process depends on your existing plan; some plans have the hot spot features built in (with limits), while others require an add-on data plan. In addition to carrier requirements, your iPhone must be running iOS 4.3 or later to be compatible with the Personal Hotspot feature.

Setup Process

Turning your phone into a virtual router is quick and easy. In the home screen, tap the "Settings" icon, choose "Network" and tap "Personal Hotspot." Slide the toggle switch so that it's showing green. At that point, you'll need to decide how you want to connect other devices to your iPhone's data connection: by a standard Wi-Fi link, Bluetooth, or USB. The option you choose will depend on the devices you want to connect. Follow the setup prompts for your connection type to enable the hot spot.

Security Considerations

Security is a serious consideration for personal hot spots. If your network is left open, any nearby user can connect to it and run down your data plan. Open connections are also easy for hackers to access, placing all of your personal information at risk. If you are using a Wi-Fi hot spot, tap "Wi-Fi Password" and create a secure password. Every device that attempts to connect to your hot spot will require the password for access.

Data Use

On AT&T, the hot spot shares the data from your data plan; if you watch movies or download large files, you can incur overages quickly. To minimize your data loss, turn the hot spot off when it is not in use. When your hot spot is active, an icon that resembles two interconnected rings appears at the top of the screen. You can keep track of your data use directly from your iPhone. In iOS 7, tap the "Settings" icon and choose "Cellular." To set the usage period back to zero, tap the "Reset Statistics" button. Reset the statistics each billing period so your data usage will be easy to track.