What Are the Ups & Downs on Tethering With the iPhone?

Tethering Plan

• The main negative of using the iPhone's tethering feature is the cost. On Verizon Wireless and AT&T, you must pay an additional $20 per month, on top of your existing data plan, to use the iPhone's Personal Hotspot app, as of July 2011. The hotspot plans on both networks are limited in the amount of data that can be used. On Verizon Wireless, the plan includes 2 gigabytes of data per month. On AT&T, it includes 4 GB.
  
  

Data Usage Charges

• If you exceed the data limitations of your 2 GB plan on Verizon Wireless or 4 GB plan on AT&T, you will incur additional charges per gigabyte exceeded, with data rounded up to the next gigabyte. On Verizon Wireless, each additional gigabyte used costs $20. On AT&T, each additional gigabyte costs $10. This means that tethered users will not be able to do much more than browse the Web without fearing an excessive use of data.
  
  

Accessibility

• Looking past the cost, the biggest benefit to tethering with the iPhone is the ability to use other devices wherever a cellular connection is available. This means that you could pull out your laptop on a road trip, tether it to your phone and have access to the Internet. You can connect your iPod touch to the Wi-Fi network broadcast from the iPhone and download new tunes from iTunes. Essentially, Personal Hotspot gives you a wireless router that you can take with you anywhere.
  
  

Limitations

• The Personal Hotspot allows up to five connections at once. This means that one person's iPhone can give five other users access to the Internet. However, the types of connections are limited by the cellphone carrier. On Verizon Wireless, all five users can connect over Wi-Fi or a mix of Wi-Fi, Bluetooth and USB. AT&T users are limited to three connections over Wi-Fi, with the remaining users having to use USB or Bluetooth. Users on Bluetooth and USB would have to be closer to the iPhone than those connecting over Wi-Fi.