Q: I have an iPhone 5 and just purchased an iPad Air with Wi-Fi only. I have an adapter that can go from my iPhone to the iPad. Will I be able to access my Internet from my iPhone to the iPad away from my house by tethering? I don’t want to purchase the $20 tethering from AT&T.
A: From a technical point of view, you can definitely tether your iPad to your iPhone for Internet access. Between iOS devices, however, this actually cannot be done with a cable; you would use either a Wi-Fi or Bluetooth connection from your iPad to your iPhone. Tethering from a Mac or Windows PC can be done using a USB to Dock Connector or USB to Lightning cable, or can also be done via Wi-Fi or Bluetooth.
Tethering is enabled on the iPhone under Personal Hotspot in the iOS Settings app, and is normally simply a matter of switching the option on. Once enabled, the iPhone will appear as a Wi-Fi access point to other nearby devices, which can connect to it using the password shown on the Personal Hotspot screen. Other devices such as your iPad are basically connecting to just another Wi-Fi network, although a special link symbol will be displayed in place of the standard Wi-Fi beacon when using an iPhone Personal Hotspot connection.
The catch, however, is that like almost all cellular features, the availability of Personal Hotspot is determined by your carrier. AT&T does include Personal Hotspot on its newer data plans, but users with the older grandfathered unlimited plans will likely be forced to either pay extra for the feature or switch to one of the newer plans that includes it.