To use your cell phone as a modem, you need the following: The device you want to be able to go online with, of course (i.e., your laptop or tablet) A data-capable cell phone that you'll use as the modem (i.e., the cell phone should be able to go online on its own) A data plan for the phone from your wireless provider. Most cellular providers these days require you to have a data plan for your smartphone anyway, but regular (or feature) phones may also be web-capable and therefore can also act as modems for your laptop. You'll need to have a data plan for the phone, whether it's a cell phone or smartphone. Tethering Options There are a few ways to use tethering so you can go online from your laptop (or tablet) using your cell phone's data plan.